A-Level · 9702 · Interactive simulations
568 unique simulations72 lessons6 sources
Every simulation here runs the real model — the same PhET, GeoGebra and physics-lab applets a teacher would put on the board, not a video of one. Pick a topic, open a card inside its lesson to run it next to the notes, or jump straight to the source. A simulation that fits several lessons is listed under each of them (879 cards in all). Back to the A Level Physics course →
Points with larger uncertainty carry less weight; one outlier can swing a gradient.
Add points, draw your own line, then compare it with the least-squares best fit.
Fire many projectiles from one launcher and analyse the landing positions with histograms, the mean and the spread.
Drop balls through a peg board and watch the bins build a binomial histogram that tends to a normal curve.
Coulomb's law for lab: collect force-distance data and fit the inverse square
Timed mass-spring oscillator for lab: change mass and k and measure the period
Resultant = tip-to-tail sum; components add independently.
Drag the tips of two vectors; see their resultant by triangle or parallelogram method
Three short animated motions; work out the distance travelled and the overall displacement for each
Enter a vector magnitude and direction; see its x and y components graphically and numerically
Twelve challenges: add three of the 25 vectors shown on the grid by components and name the resultant
Subtract vectors graphically and read the resulting components
Set magnitude/direction of two vectors with sliders; toggle to show sum or difference vector
Practice worksheet: draw the sum or difference of two given vectors, then check the answer
Set boat heading, boat speed and river speed; watch the resultant path across the river
Drag up to three vectors onto the canvas, turn each arrowhead to set its direction, guess the resultant, then tap to draw it
Watch a person hike a two-dimensional path, then give the distance and the displacement (magnitude and direction); pass levels to progress
Cross a river in a boat: set the boat speed, the river speed and the heading, then watch the resulting motion and read the crossing time
Balance an angled force with forces that lie along the x- and y-axes; the Help page walks through resolving it into components
A 747 lands with the wind blowing across the runway; the nose is held at a crab angle and the three velocity vectors are drawn as they add
Drag vectors around and see the resultant form head to tail, with the component breakdown shown alongside
A pen runs straight along a ruler while the paper is pulled away at right angles; the slanted line is drawn as it happens
Set boat speed and heading against a river current to reach a drowning swimmer; compare routes and times
Point a boat across a flowing river; adjust heading to find the resultant velocity
Relative velocity in two dimensions with adjustable vectors
Drag two vectors and see their head-to-tail sum and components
Place a block on a tilted surface and watch the normal force component change with angle
Drag two 2D vectors (or set magnitude, angle, scalar multiplier, operation) and see sum, difference, dot product, components, magnitude and direction
Drag a ladybug across the screen and see its velocity and acceleration vectors drawn as it moves.
Steer a ball through a maze by controlling its position, velocity or acceleration vector.
Two random vectors appear; decide the size and direction of the resultant before the 20-second timer runs out
A short demonstration: add the same vectors in different orders and compare the magnitude and direction of the resultant
Resize a right triangle while keeping its angles fixed and watch sine, cosine and tangent stay put
A moped leaves a trail of dots; set the initial velocity, acceleration and time and watch the position-, velocity- and acceleration-time graphs
Set velocity and acceleration for linear motion; read x-t, v-t and a-t graphs
Shape a straight-line v-t graph by dragging points; read off displacement, acceleration and motion
Fire a cannon with chosen speed and angle; trace the path with or without air resistance.
Match 11 animated motions to their position-time and velocity-time graphs
Drag the man along the line, or type in position, velocity and acceleration, and watch all three graphs update together.
Set boat heading, boat speed and river speed; watch the resultant path across the river
Adjust initial position, velocity and acceleration; watch the motion and its x-t, v-t, a-t graphs together
Slide points on a v-t graph; the x-t and a-t graphs update to match the motion
Set initial position/velocity then adjust acceleration; see x-t, v-t and a-t graphs of the object
Adjust x0, v0 and a for a car under uniform acceleration; run and watch the resulting motion and data
Two cars with independent x0, v0 and a; run to see when and where they meet
Change launch speed, angle and height; watch the trajectory, velocity components and range
Compare four projectiles launched at 20/30/45/60 degrees over level ground; toggle vectors and paths
Three short animated motions; work out the distance travelled and the overall displacement for each
Cross a river in a boat: set the boat speed, the river speed and the heading, then watch the resulting motion and read the crossing time
Match 11 animated motions to their verbal descriptions by identifying the direction of the velocity and acceleration vectors
Print the ArUco marker, point your phone at it and walk; your position is plotted live so you can match a position-time graph
Walk in front of the printed ArUco marker and match 15 velocity-time graphs plotted live from your motion
Given a position-time graph, pick the matching velocity-time graph, acceleration-time graph and motion diagram
Build a ramp so a rolling ball reproduces a given position-time or velocity-time graph; the motion is plotted live as the ball rolls
Simulate a two-stage rocket and watch its position-time and velocity-time graphs drawn in real time
Set the x- and y-velocity and acceleration components separately and watch the resulting diagonal motion
Projectile motion with air resistance: set the launch and drag parameters and compare the trajectory with the no-drag case
Modify the launch height, launch angle and launch speed and observe the effect on the trajectory
Launch a projectile at an angle over level ground, horizontally or at an angle from a cliff, or from the ground towards a cliff
A cannon fires horizontally from a cliff; determine the cliff height, the launch speed or the target location so the ball hits
An object moves along a line while position, velocity and acceleration graphs are drawn together; change the motion and all three update
A jet in level flight releases a bomb; the parabola seen from the ground and the vertical line seen by the pilot are drawn side by side
A pen runs straight along a ruler while the paper is pulled away at right angles; the slanted line is drawn as it happens
Drop objects of different masses together with no air resistance while position, velocity and acceleration are plotted in real time
Manipulate any one of the position, velocity or acceleration graphs and watch the other two update to stay consistent
The horizontal and vertical components are plotted alongside the trajectory; change the launch angle and watch the range respond
Objects moving uniformly run alongside objects whose velocity changes, with graphs that make the distinction precise
Set boat speed and heading against a river current to reach a drowning swimmer; compare routes and times
Point a boat across a flowing river; adjust heading to find the resultant velocity
Relative velocity in two dimensions with adjustable vectors
Launch a ball vertically from a moving cart and see it land back in the cart
Step through motion with changing acceleration and watch the x, v, a graphs
Tilt Galileo's inclined plane and release a ball; collect distance-time data to show constant acceleration
Brake a boat with chosen deceleration and find the stopping distance
Set thrust and takeoff speed; compute runway length from the SUVAT equations
Set launch angle, speed, height, gravity and drag; trace the path and inspect range, time and height
Fire a dart at a monkey that drops at the instant of firing; vary speed and see why it always hits
Enter launch parameters and solve a full projectile problem with worked numbers
Drag a moving object and see linked position, velocity and acceleration graphs
Ball falls and bounces; adjust g, mass, wind acceleration, friction coefficient and restitution to compare free fall, weight vs mass and energy loss per bounce
Launch a projectile; set launch speed, angle, start height, g, quadratic drag and wind; read range, max height and time of flight against the drawn trajectory
Draw a function with the pen and watch its derivative and integral curves update live.
Fire many projectiles from one launcher and analyse the landing positions with histograms, the mean and the spread.
Drag a ladybug across the screen and see its velocity and acceleration vectors drawn as it moves.
Steer a ball through a maze by controlling its position, velocity or acceleration vector.
Classic monkey-hunter: aim the dart at a monkey that drops when fired; shows why aiming directly works
Use your device camera as a motion detector: track an object and plot its position against time in real time
Drag out a motion path with your mouse or finger and view the x-position and y-position as functions of time
Use your mobile device as an accelerometer and plot its acceleration against time
Record or upload a video, mark an object's path frame by frame and read off velocities, accelerations and data points
Stop Birdman with projectile problem-solving: the height sets the fall time and the horizontal speed sets where the drop lands
Birdman's Turd-a-Pault launches at an angle; use projectile problem-solving on the launch speed and angle to stop the landing
Aim a banana cannon at a monkey that drops from the tree the moment you fire; set the aim and the launch speed
A motion diagram builds as an object moves in three dimensions; rotate it freely to compare the velocity and acceleration directions
Uniform, accelerated, oscillatory and circular motion run side by side so their graph traces can be compared
Aim a cannon at a moving alien target; a projectile-motion game
Race two boats with different frames; compare relative speeds
Car and speedboat racing: compare relative velocity along parallel paths
Eject a man from a moving truck; compare velocities in ground and truck frames
Relative velocity in one dimension with two moving objects
F = ma: net force, not applied force, sets acceleration; zero net force means constant velocity.
Adjust applied force and mass on a cart; read acceleration and compare with F = ma
Explore which variables give a safe landing or a broken egg: drop height and the landing surface
Collide carts of chosen mass and velocity in 1D or 2D; read momenta before and after.
Ride an accelerating elevator and read apparent weight on the scale
Vary the sledder's mass, the parachute size, the applied force and the friction; speed, acceleration and force values display as it moves
Push a crate or fridge with a chosen applied force; read friction, net force, and the acceleration and velocity graphs.
Push a crate or fridge across a surface with chosen friction; see the free-body diagram and the force, velocity and acceleration graphs.
Push objects up a ramp; vary the angle, friction and mass and read the work done, energy bar charts and force graphs.
Pull a box with a rope at adjustable tension/angle; explore static vs kinetic friction and normal force
Vary incline angle (0-90) and friction coefficients; see weight, normal and friction vectors and the motion
Atwood-style system: mass on a rough incline linked over a pulley to a hanging mass; run to see the motion
Set the angle, mass, initial velocity and coefficients of static and kinetic friction; observe the forces, motion and energy changes
Newton's second law with one or two objects in one or two dimensions; add each nuance step by step and compare the acceleration
Push a box across a surface; alter the applied force, the mass and the friction and investigate the acceleration
Construct free-body diagrams for 12 situations: select up-down-right-left force types and tap the arrows to set their magnitudes
Twelve new situations for building free-body diagrams: select the force types and tap the arrows to set their magnitudes
Ride an elevator and explore the physics of weightlessness and weightiness as it starts and stops
Hang two objects over a pulley or build a modified Atwood's machine; change the mass on either object and introduce friction
Increase applied force on a block to see static friction give way to kinetic friction
Set two Atwood masses and measure acceleration; compare with theory
Atwood machine worked problem with adjustable masses
Force and friction problem on a block with adjustable coefficients and pull angle
Newton's second law worked problem with adjustable force, mass and friction
Place a block on a tilted surface and watch the normal force component change with angle
Block on a ramp; set mass, plane angle, static and kinetic friction coefficients, applied force and g; find the angle where static friction fails (tan θ = μs)
Push objects up a ramp of adjustable angle and friction; see the forces, the work done and the energy bar charts.
Speed stops increasing once the drag force equals the weight.
A numerical model of a fall with air resistance: set the mass, initial height, initial velocity, profile area, drag coefficient and air density
Switch air resistance on and compare the same launch with and without drag.
Vary the sledder's mass, the parachute size, the applied force and the friction; speed, acceleration and force values display as it moves
Drop spheres through fluids of different viscosity; see terminal velocity
Push a crate or fridge with a chosen applied force; read friction, net force, and the acceleration and velocity graphs.
Push a crate or fridge across a surface with chosen friction; see the free-body diagram and the force, velocity and acceleration graphs.
Projectile motion with air resistance: set the launch and drag parameters and compare the trajectory with the no-drag case
Objects moving uniformly run alongside objects whose velocity changes, with graphs that make the distinction precise
Set launch angle, speed, height, gravity and drag; trace the path and inspect range, time and height
Ball falls and bounces; adjust g, mass, wind acceleration, friction coefficient and restitution to compare free fall, weight vs mass and energy loss per bounce
Launch a projectile; set launch speed, angle, start height, g, quadratic drag and wind; read range, max height and time of flight against the drawn trajectory
Draw a function with the pen and watch its derivative and integral curves update live.
Momentum conserved in every collision; KE conserved only when perfectly elastic.
Collide two carts with adjustable masses, speeds and elasticity; read momentum and KE before and after
Two carts on a low-friction track push apart with a spring-loaded plunger; vary the relative mass and compare the speeds
A brick drops onto a moving cart; use the position-time data to find speeds before and after and compare the momentum totals
Collide objects in two dimensions and analyse momentum conservation in each direction
Perfectly elastic collision problem with adjustable masses; check both momentum and KE conservation
1D collision of two masses: set masses, velocities and elasticity; compare momentum and KE before/after
Two boxes pushed apart by an explosive charge; set masses, initial velocity and explosion energy
Ballistic pendulum: set bullet/block masses and bullet speed; see inelastic collision then rise height
Ballistic pendulum quiz: given masses and rise height, compute the bullet speed and check it
Person walks along a floating raft; adjust masses and watch raft recoil so the centre of mass stays fixed
Two bullets fired upward into identical blocks, one at centre, one off-centre; compare heights reached
A big fish catches a smaller one; explore how the relative masses predict the post-collision speed
Slam carts together on a track, or explode them apart with a firecracker; change the mass and velocity and read the before-and-after data
Eight collision scenarios; manipulate the variables and look for patterns in the outcomes
Elastic and inelastic collisions run side by side with momentum and kinetic energy totalled before and after
Fire a bullet into a hanging block; use swing height to find the bullet speed
Solve a 1D collision exercise with your own masses and velocities
Set up a 2D billiard-ball collision and resolve momentum in two directions
Fire a bullet into a block; vary masses and speed and confirm momentum is conserved
Lift and release Newton's cradle balls; see momentum and energy pass through the chain
Two bodies collide on a line; set each mass and initial velocity plus the coefficient of restitution and read momentum and kinetic energy before and after
Drop a second mass onto an oscillating spring-mass at equilibrium or max displacement; compare amplitude/period changes
Ball at constant velocity rebounding off walls; set mass, diameter, gravity and coefficient of restitution and watch one velocity component flip at each wall
Moment = force × perpendicular distance; balance when the two sums are equal.
One to four torques are placed on the right of the fulcrum; add torques on the left to balance the beam and check your answer
Balance a beam with known masses to deduce the beam's own mass from moments
Drag out a shape, view its centre of mass as you change it, then hang it on the corkboard and watch it swing about the pivot
Tilt objects to explore stability, equilibrium and where the centre of mass must sit over the base
Two equal and opposite forces produce pure rotation with no net force; move the measuring point and the turning effect is unchanged
Uniform bar hinged at one end, held by a cable, with a movable mass; find cable tension and hinge force
Hang weights at different positions on a balance beam and work out what it takes to balance
A rod leans against a wall; control the lengths, masses and angles and see how each affects the forces
Apply a force to a wheel at any point and any angle and see how the perpendicular distance to the axle governs the turning effect
Hang masses on a beam at chosen positions to balance it about a pivot
Static equilibrium problem 1: adjust forces and solve for unknown tensions
Static equilibrium problem 2 with a hinged beam and cable
Static equilibrium problem 3 with multiple supports
Place point masses on a 2D grid; compute and move the centre of mass
Place masses in 3D space and locate the combined centre of mass
Equilibrium: forces form a closed triangle/polygon; components sum to zero in each direction.
Drag out a force vector to balance the given one, then level up to balancing two and then three force vectors
Add gold coins to a bag hanging from ropes without breaking them; the rope angles set the tension, and levels get harder
Hang masses on a beam at chosen positions to balance it about a pivot
A rod leans against a wall; control the lengths, masses and angles and see how each affects the forces
Balance an angled force with forces that lie along the x- and y-axes; the Help page walks through resolving it into components
Push objects up a ramp; vary the angle, friction and mass and read the work done, energy bar charts and force graphs.
Pull a box with a rope at adjustable tension/angle; explore static vs kinetic friction and normal force
Vary incline angle (0-90) and friction coefficients; see weight, normal and friction vectors and the motion
Uniform bar hinged at one end, held by a cable, with a movable mass; find cable tension and hinge force
Tilt objects to explore stability, equilibrium and where the centre of mass must sit over the base
Set the angle, mass, initial velocity and coefficients of static and kinetic friction; observe the forces, motion and energy changes
Construct free-body diagrams for 12 situations: select up-down-right-left force types and tap the arrows to set their magnitudes
Twelve new situations for building free-body diagrams: select the force types and tap the arrows to set their magnitudes
Increase applied force on a block to see static friction give way to kinetic friction
Force and friction problem on a block with adjustable coefficients and pull angle
Tilt a ramp until a block just slips; compute the static friction coefficient from the angle
Balance a beam with known masses to deduce the beam's own mass from moments
Static equilibrium problem 1: adjust forces and solve for unknown tensions
Static equilibrium problem 2 with a hinged beam and cable
Static equilibrium problem 3 with multiple supports
Hang a charged ball on a string in a uniform field; find the deflection angle
Drag two 2D vectors (or set magnitude, angle, scalar multiplier, operation) and see sum, difference, dot product, components, magnitude and direction
Block on a ramp; set mass, plane angle, static and kinetic friction coefficients, applied force and g; find the angle where static friction fails (tan θ = μs)
Push objects up a ramp of adjustable angle and friction; see the forces, the work done and the energy bar charts.
ρ = m/V decides floating, not mass alone; blocks denser than water sink.
Move a probe to different depths; read pressure and confirm p = rho g h
U-tube with two fluids; use column heights to find an unknown density (explore and lab modes)
Weigh blocks in air and in fluid; read the buoyant force and the fluid displaced.
Submerge objects of different densities; read displaced volume and upthrust
Differently shaped vessels filled to the same height stand side by side; compare the gauge readings at their bases
Measure pressure at depth in fluids, then explore flow through pipes and a water tower.
Adjust fluid density, object density and viscosity; run to see sinking, floating and the buoyant force
Lab: weigh an object in air and submerged in a known fluid, compute its density and check
Place an object in a fluid and see the forces at play; set its density to decide whether it floats or sinks
Choose the densities of two liquids that do not mix and see the U-tube column heights adjust until the pressures balance
Probe the pressure at any point inside oddly shaped containers and plot it against depth
Weigh an object in air then in fluid; relate apparent weight to upthrust
Second apparent-weight experiment with changeable fluids
Change fluid density and submerged volume; read the buoyant force
Weigh a submerged object and compare loss of weight with displaced fluid weight
Drop objects into fluids of adjustable density; see float or sink
Measure mass and volume of a sample to compute density
Submerge an object in a full beaker and measure overflow volume
Compare blocks of different mass and density in a pool: which float, which sink, and how much fluid each displaces.
Compare densities of water and ice and see why ice floats
Total energy is constant; friction converts mechanical energy to thermal, never destroys it.
Drive a car up a gently-sloped hill and a steep hill to the same summit and compare the work and energy
Push a block across a rough floor; compare work done by force and by friction with the KE change
Relate the work done on an object to the kinetic energy it acquires, and see what friction changes
Slide a block down a ramp with chosen height and friction; track energy transfers
Build work-energy bar charts that show what happens to the total energy of an object and how its form changes
Push objects up a ramp; vary the angle, friction and mass and read the work done, energy bar charts and force graphs.
1D collision of two masses: set masses, velocities and elasticity; compare momentum and KE before/after
Ballistic pendulum: set bullet/block masses and bullet speed; see inelastic collision then rise height
Ballistic pendulum quiz: given masses and rise height, compute the bullet speed and check it
Mass oscillating on a vertical spring with live KE / GPE / EPE bar graphs; adjust mass and spring constant
Set the angle, mass, initial velocity and coefficients of static and kinetic friction; observe the forces, motion and energy changes
Skid a car to a stop from different speeds and compare the stopping distances
Build a first drop, a loop, or dips and hills and study the coaster's energy and speed along the track
Apply a force over a distance and track the work done and the kinetic energy as the motion proceeds
Fire a bullet into a hanging block; use swing height to find the bullet speed
Roll a double cone up a diverging V-track; see why its centre of mass actually falls
Drop or launch an object and watch KE, PE and total energy bars update in real time
Swing a pendulum and watch PE convert to KE and back through the cycle
Compress or stretch a spring and watch the stored elastic energy change with extension
Release a cart from a chosen height into a vertical loop; find the minimum height to stay on track
Two bodies collide on a line; set each mass and initial velocity plus the coefficient of restitution and read momentum and kinetic energy before and after
Push objects up a ramp of adjustable angle and friction; see the forces, the work done and the energy bar charts.
Simple pendulum: adjust length, initial angle and g; examine forces, acceleration, velocity and energy
mgh → ½mv² exchange; the mass cancels so the speed depends only on height dropped.
Drop or launch an object and watch KE, PE and total energy bars update in real time
Skid a car to a stop from different speeds and compare the stopping distances
Slide a block down a ramp with chosen height and friction; track energy transfers
Build a first drop, a loop, or dips and hills and study the coaster's energy and speed along the track
Swing a pendulum and watch PE convert to KE and back through the cycle
Mass oscillating on a vertical spring with live KE / GPE / EPE bar graphs; adjust mass and spring constant
Relate the work done on an object to the kinetic energy it acquires, and see what friction changes
Drive a car up a gently-sloped hill and a steep hill to the same summit and compare the work and energy
Apply a force over a distance and track the work done and the kinetic energy as the motion proceeds
Fire a bullet into a hanging block; use swing height to find the bullet speed
Roll a double cone up a diverging V-track; see why its centre of mass actually falls
Push a block across a rough floor; compare work done by force and by friction with the KE change
Ball falls and bounces; adjust g, mass, wind acceleration, friction coefficient and restitution to compare free fall, weight vs mass and energy loss per bounce
F = kx: a straight-line force–extension graph; the gradient is the spring constant.
Hang masses on a spring and plot force against extension to find k
Hang masses on springs, measure the stretch with the ruler and time the period with the stopwatch.
Compress or stretch a spring and watch the stored elastic energy change with extension
Elastic potential energy = area under F–x = ½Fx = ½kx².
Compress or stretch a spring and watch the stored elastic energy change with extension
Hang masses on a spring and plot force against extension to find k
Mass oscillating on a vertical spring with live KE / GPE / EPE bar graphs; adjust mass and spring constant
Shake a string by hand, pulse or oscillator; set tension, damping and frequency.
Sixty particles connected by springs; vibrate the first one at a regular rate and explore the wave that results
Water, sound and light waves from one source; measure wavelength and amplitude.
Compare two SHM oscillators / waves with an adjustable phase shift between them
Move away from a source and read intensity versus distance
Side-by-side longitudinal and transverse waves; adjust amplitude and frequency and read off wavelength
Tutorial page (GIF animations, no applet): definitions of wave, medium, transverse vs longitudinal
Tutorial with applet: period, frequency, amplitude, wavelength and v = f lambda on a travelling wave
Two wave pulses pass through each other; adjust heights/widths and watch the superposed sum
Link SHM, uniform circular motion and a transverse wave side by side with sliders and checkboxes
A marker on a turntable oscillates one cycle per turn and traces a sine wave, with 3D viewing
A virtual wave machine: watch the periodic motion of the rods and the wave travelling along them
Wiggle a particle on a string; change the wiggle frequency, the amplitude and the damping and watch the disturbance travel
Waves spread as expanding surfaces in 3D; place obstacles and boundaries and watch the wavefronts reflect and refract
Displacement against distance and displacement against time are drawn together for the same wave
Choose transverse or longitudinal, set the frequency and amplitude, and watch the wave carry energy without carrying the medium
Watch oscillating E and B fields propagate as an electromagnetic wave
Overlay two travelling waves with adjustable frequency and phase
Set the amplitude of each sine harmonic and watch the summed waveform build; a wave-packet screen goes further.
Surface (water) wave with adjustable amplitude, wavelength and speed; show the circular particle motion
Pulse reflecting from a fixed or free end; toggle incident/reflected components and phase inversion
Capture sound from your microphone and display the wave with an estimated pascal pressure and time readout at any point
Capture sound from any source and display its spectrogram and FFT over time
A tuning fork's vibration is coupled to a spring so the resulting travelling wave can be measured
A slider each for amplitude, frequency and phase; isolate the effect of one at a time on a sine curve
Wavelength shortens as frequency rises and is unaffected by amplitude; particles move across the wave in one and along it in the other.
Watch pressure fronts leave a speaker; move a listener and show the pressure graph.
Sixty particles connected by springs; vibrate the first one at a regular rate and explore the wave that results
A transverse wave you can freeze — watch one point of the string move.
Wiggle a particle on a string; change the wiggle frequency, the amplitude and the damping and watch the disturbance travel
Transverse and longitudinal waves run along the same spring so the particle motions can be compared directly
Tutorial page (GIF animations, no applet): definitions of wave, medium, transverse vs longitudinal
Longitudinal travelling or standing wave; adjust speed and amplitude; see compressions and rarefactions
Air-column resonance shown with longitudinal particle displacement and pressure representations
Choose transverse or longitudinal, set the frequency and amplitude, and watch the wave carry energy without carrying the medium
Individual particles are tracked so you can see them oscillating in place while the compressions move along
Air molecules bunch and spread while the pressure trace a microphone would record is drawn; change the frequency and amplitude
Watch oscillating E and B fields propagate as an electromagnetic wave
Surface (water) wave with adjustable amplitude, wavelength and speed; show the circular particle motion
Tutorial page (text only): sound as a longitudinal wave, speed of sound in air
A tuning fork's vibration is coupled to a spring so the resulting travelling wave can be measured
Wavefronts bunch ahead of a moving source so the observed frequency rises; above the wave speed they overlap into a cone.
Move a sound source past a listener; hear and see the frequency shift
Tutorial with applet: moving source/observer, apparent frequency shift and sonic boom
Wavefronts bunch ahead of a moving source and stretch out behind it; set the source speed and watch
Frequency rises as wavelength falls across the spectrum.
Animated EM wave with oscillating E (green) and B (red) field vectors perpendicular to propagation
Slide the temperature of a glowing body and watch its spectrum move across the EM bands.
Shine red, green and blue bulbs, or a single filtered beam, at a viewer and see the colour they perceive.
Oscillate the electron in a transmitting antenna, by hand or sinusoidally, and watch the radiated electric field reach the receiver.
Shine microwave, infrared, visible or UV light at CO₂, H₂O, N₂, O₂ and other molecules and see which absorb and vibrate.
The electric and magnetic field vectors of a wave are drawn in 3D as it propagates
Watch oscillating E and B fields propagate as an electromagnetic wave
Send microwaves at water molecules and watch them rotate; view the oscillating electric field as arrows or a curve.
Spark a transmitter and detect the EM wave at a receiving loop, as Hertz did
Reproduce Romer/Huygens' speed-of-light estimate from Jupiter's moons
Measure the speed of light with a rotating mirror or chopper wheel
Transmitted amplitude follows the cosine of the filter angle and drops to zero at 90°.
Rotate a polariser and plot transmitted intensity against angle (Malus's law)
Rotate a Polaroid filter over a photograph and see how the reflected glare changes
The electric and magnetic field vectors of a wave are drawn in 3D as it propagates
Fix the far end, drive the string and tune the frequency until nodes stand still.
Drive a string at chosen frequency; see nodes and antinodes form
Two waves travel in opposite directions; use the pre-set conditions or set your own and view the standing wave
Standing waves on a string: vary driving frequency, linear density and tension to hit harmonics
Sound resonance in open/closed air columns: see incident and reflected waves build a standing wave
Longitudinal travelling or standing wave; adjust speed and amplitude; see compressions and rarefactions
Two transverse waves travelling in opposite directions; adjust speed/wavelength and see the resulting standing wave
Standing waves on a string or in open/closed air columns; show the two travelling components and particle motion
Air-column resonance shown with longitudinal particle displacement and pressure representations
Tutorial with applet: oppositely travelling waves of equal wavelength form a standing wave
Tutorial page (GIF animations, no applet): first three harmonics on a string, wavelength-length relations
Tutorial page (GIF animations, no applet): harmonics in an open-open air column
Tutorial with applet: harmonics in a closed-open air column (odd harmonics only)
Tutorial with applet: explore standing waves in air columns interactively
Tutorial with applet: wave speed on a string from tension and linear density; harmonic frequencies
Two waves travel through the same medium; see the interference and the resultant at each point
A standing wave forms in an air column; change its length to hear and see the resonant frequency shift
A wave is sent along a string and reflected back; nodes and antinodes form where the two waves superpose
Overlap two waves you control and watch the resultant, from total cancellation to doubled amplitude
Excite the first few modes of a string of masses and see each standing-wave shape.
Pulse reflecting from a fixed or free end; toggle incident/reflected components and phase inversion
Tutorial with applet: transmission, reflection and inversion at a boundary between media
View incident, reflected and transmitted pulses and see how their speed, wavelength and amplitude depend on the density of each medium
Diffraction is strongest when the gap is about one wavelength.
Change slit width and wavelength to see the single-slit diffraction pattern
Watch wavelets build the new wavefront after refraction or diffraction
Place barriers, gaps and different depth regions in a ripple tank and watch waves reflect, refract and diffract
Double slit: vary wavelength, slit separation, slit width and screen distance; see fringe pattern and intensity
Waves spread as expanding surfaces in 3D; place obstacles and boundaries and watch the wavefronts reflect and refract
Fringe spacing ∝ λ/d; constructive where path difference = nλ.
Two waves travel through the same medium; see the interference and the resultant at each point
Two point sources vibrate in a ripple tank; view the pattern and find the nodal and antinodal lines
Make a few simple measurements on a two-slit pattern and calculate the wavelength of light
Change slit separation and wavelength; see the double-slit fringe pattern
Overlay two travelling waves with adjustable frequency and phase
Two transverse waves travelling in opposite directions; adjust speed/wavelength and see the resulting standing wave
Tutorial with applet: oppositely travelling waves of equal wavelength form a standing wave
Two wave pulses pass through each other; adjust heights/widths and watch the superposed sum
Two pulses on one string in opposite directions; the bottom string shows their point-by-point sum
Draw or pick two pulse shapes, predict the superposition and then check it
Two-source surface-wave interference in 3D; adjust frequency, source separation and amplitude
Tutorial with applet: superposition of overlapping pulses, constructive and destructive interference
Tutorial with applet: superposition patterns of two continuous waves travelling the same direction
Double slit: vary wavelength, slit separation, slit width and screen distance; see fringe pattern and intensity
Double slit with wavefronts: adjust slit separation and wavelength; show maxima and scale
Change the wavelength or the distance between two sources and explore the resulting interference pattern
Place barriers, gaps and different depth regions in a ripple tank and watch waves reflect, refract and diffract
Two sources vibrating in step produce a fixed pattern of reinforcement and cancellation; move the sources apart and watch the fringes
Vary the slit spacing and the wavelength while the fringe pattern on the screen adjusts in real time
Overlap two waves you control and watch the resultant, from total cancellation to doubled amplitude
Two point sources in a ripple tank; see constructive and destructive interference
Spot angles satisfy d sin θ = nλ, so higher orders sit at larger angles.
Light through two then more slits — see how extra slits sharpen each order.
Change slit width and wavelength to see the single-slit diffraction pattern
Current is the same all along a series loop and splits at a junction (Σ I in = Σ I out).
Close a switch on a long loop of wire and watch every electron start moving at once while each one drifts slowly.
Vary the battery voltage and the resistance; watch electrons move through the resistor and the resistor heat up.
One wire with three thicknesses and a counter at each; squeeze the middle section and watch the carrier speed and the three counters
Measure the electron charge from mass deposited in electrolysis
A virtual circuit board: add resistors, bulbs, wires and ammeters, use a voltmeter, and build series, parallel and combination circuits
A metal, an electrolyte, a semiconductor and an ionised gas side by side, each with its own carriers moving inside
Dial in a charge and watch it divided by the elementary charge; a whole number shows that many electrons, a fraction shows what cannot exist
Switch between the conventional picture and the electron picture and the four-cell table shows the direction inside and outside the source
Two taps fill two buckets against two stopwatches; hold the time and double the charge, or hold the charge and double the time
Three graphs on draggable axes: the slope of Q–t, the slope of N–t and the area under I–t
Free electrons in a copper loop move at around 10⁶ m/s with no net motion; switch the field on and a slow drift appears on top
Count the charge crossing a marked section of wire and divide by the time; the same flow reads in coulombs per second and electrons per second
Copper's electron shells fill 2, 8, 18, then one lone electron in the outer shell; see why the smallest nudge sets it free
Eggs hop one cup at a time along a carton with a single empty cup; watch the eggs go one way and the gap walk the other
A water circuit runs alongside an electric one: pumps for cells, narrow pipes for resistors, flow rate for current
A 3D copper lattice: Cu⁺ cores vibrate about fixed sites while free electrons move in the gaps between them
Positive and negative carriers cross the same section at once; each negative carrier has its sign and direction flipped before being added in
Rain falls into collectors and drains through pipes to build a mental model of charge, current and potential difference
Close the switch and the field sweeps round the loop near light speed while the electrons barely crawl
V = W/Q: p.d. shares out the battery energy; P = IV sets brightness.
Ohm's law applied to resistors in series with meters
A 3D bench of appliances: read each rating plate, work out R from V²/P, and compare the three power formulae, including the motor
Slide voltage and resistance; the current readout and formula resize live.
Turn the battery voltage up and down and watch charges separate onto the two terminals.
A virtual circuit board: add resistors, bulbs, wires and ammeters, use a voltmeter, and build series, parallel and combination circuits
A 3D circuit with an earth rod and a landscape of potential above it; move the earth clip and the landscape slides without any difference changing
Vary voltage and resistance; read current and plot V-I
Ohm's law applied to resistors in parallel with meters
Four DC circuits; set each EMF, internal resistance and the three resistances, drag a voltmeter and ammeter on; watch the KCL and KVL sums balance to zero
A water circuit runs alongside an electric one: pumps for cells, narrow pipes for resistors, flow rate for current
R = ρL/A: long, thin, high-resistivity wires resist most.
Slide voltage and resistance; the current readout and formula resize live.
Vary voltage and resistance; read current and plot V-I
Heat a resistor and watch resistance change with temperature
Inside a 3D copper sample an electron zig-zags between vibrating ion cores with its collisions counted; raise the temperature and watch R
Shine light on a metal, an insulator or a photoconductor and watch electrons move between energy bands and conduct.
Vary the battery voltage and the resistance; watch electrons move through the resistor and the resistor heat up.
A 3D Ohm's law bench: switch, rheostat, ammeter and resistor in series, voltmeter across the resistor; each setting adds a V–I point
Ohm's law applied to resistors in parallel with meters
Ohm's law applied to resistors in series with meters
Vary wire length, area and material; read resistance and resistivity
A 3D copper lattice: Cu⁺ cores vibrate about fixed sites while free electrons move in the gaps between them
Terminal p.d. = E − Ir: more current drawn → bigger drop across internal resistance.
Four DC circuits; set each EMF, internal resistance and the three resistances, drag a voltmeter and ammeter on; watch the KCL and KVL sums balance to zero
Resistors in series: see current shared and voltage divided
Resistors in parallel: see voltage shared and current divided
Combination circuit with four identical bulbs and three switches; predict then test brightness and current
Real components on a bench: click any one to see its symbol, slide the rheostat to share out the 12 V, and push the current through
A virtual circuit board: add resistors, bulbs, wires and ammeters, use a voltmeter, and build series, parallel and combination circuits
A 3D Ohm's law bench: switch, rheostat, ammeter and resistor in series, voltmeter across the resistor; each setting adds a V–I point
Build resistor networks and watch the live current and voltage readings update as you go
Eight drawings of parallel resistors: gather every starting end at node a and every finishing end at node b and check each branch
Ohm's law applied to resistors in parallel with meters
Ohm's law applied to resistors in series with meters
Construct DC circuits with batteries, bulbs and meters
Build resistor combinations and compute the equivalent resistance
Traffic passing through toll gates replaces the algebra: see why adding a parallel resistor lowers the total resistance
Currents into each junction sum to zero and the voltages around each loop sum to the EMF.
Drag batteries, bulbs, resistors and meters onto a board; watch electrons flow.
Resistors in parallel: see voltage shared and current divided
Resistors in series: see current shared and voltage divided
Given a series, parallel or combination circuit, choose resistor values that produce a target equivalent resistance
Combination circuit with four identical bulbs and three switches; predict then test brightness and current
A virtual circuit board: add resistors, bulbs, wires and ammeters, use a voltmeter, and build series, parallel and combination circuits
Eight drawings of parallel resistors: gather every starting end at node a and every finishing end at node b and check each branch
Ohm's law applied to resistors in parallel with meters
Ohm's law applied to resistors in series with meters
Construct DC circuits with batteries, bulbs and meters
Build resistor combinations and compute the equivalent resistance
Resistor combination problem 3
Balance a Wheatstone bridge to find an unknown resistance
Two resistors in series as a divider; move the voltmeter to read the share across each.
Four DC circuits; set each EMF, internal resistance and the three resistances, drag a voltmeter and ammeter on; watch the KCL and KVL sums balance to zero
Real components on a bench: click any one to see its symbol, slide the rheostat to share out the 12 V, and push the current through
Balance a Wheatstone bridge to find an unknown resistance
A 3D circuit with an earth rod and a landscape of potential above it; move the earth clip and the landscape slides without any difference changing
Most alphas pass straight through; a tiny, dense, positive nucleus explains the rare large angles.
Add protons and neutrons to a nucleus and watch which decays it undergoes.
Watch an alpha particle tunnel out of a heavy nucleus
Watch a neutron become a proton with beta and antineutrino emission
See an excited nucleus de-excite by emitting a gamma photon
Watch hydrogen-3 or carbon-14 nuclei undergo beta decay, emitting an electron and an antineutrino, with half-life timing.
Fire alpha particles at gold foil; count scattering angles and infer the nucleus
Drag protons, neutrons and electrons into an atom; read element, charge and mass number.
Watch hydrogen-3 or carbon-14 nuclei undergo beta decay, emitting an electron and an antineutrino, with half-life timing.
Dial in a charge and watch it divided by the elementary charge; a whole number shows that many electrons, a fraction shows what cannot exist
Both bugs share the angular speed, and linear speed is proportional to radius.
Spin a turntable with a ladybug on it and read angular position, velocity and acceleration alongside the linear values.
Object in uniform circular motion; set radius, tangential speed, mass and size and watch the velocity (tangent) and centripetal acceleration (inward) vectors
An angle at the centre of a circle is tied to the arc it cuts, showing that arc divided by radius is the angle in radians
Fly a drone around a circular tunnel and inspect velocity and acceleration vectors
Change the mass, speed or radius and see the velocity, acceleration and net force on an object moving in a circle
Drag an object, or pick circular or elliptical motion, and watch the velocity and acceleration vectors.
Conical pendulum: adjust radius and view; see tension and weight resolving to give centripetal force
The velocity and acceleration vectors are drawn as an object circles at steady speed
Spin a turntable with a disk on it; find the speed at which friction can no longer hold it
Drive a car on a banked curve; find the speed at which no friction is needed (banked up)
Second banked-road case with the friction direction reversed
Swing a mass in a horizontal circle; vary radius, speed and mass and read the centripetal force
Solve a net-inward-force problem with adjustable radius, speed and mass
Release a cart from a chosen height into a vertical loop; find the minimum height to stay on track
A planet in a circular orbit — show the velocity and gravity vectors as it goes round.
Drive a car round an oval using force buttons to accelerate, decelerate and turn; stay on the track in as few moves as possible
Acceleration points to the centre with magnitude v²/r; the velocity vector stays tangent.
Change the mass, speed or radius and see the velocity, acceleration and net force on an object moving in a circle
Swing a mass in a horizontal circle; vary radius, speed and mass and read the centripetal force
Conical pendulum: adjust radius and view; see tension and weight resolving to give centripetal force
A ball on a light string, a rigid rod or a loop wall moves in a vertical circle; change a variable and observe the tension and speed
A planet in a circular orbit — show the velocity and gravity vectors as it goes round.
Drag an object, or pick circular or elliptical motion, and watch the velocity and acceleration vectors.
Spin a turntable with a ladybug on it and read angular position, velocity and acceleration alongside the linear values.
3D conical pendulum: adjust string length, velocity and view angle; relate speed to cone angle
A ball on a string, a car on a banked turn and a plane in a horizontal circle; change a variable and observe its effect
Change the design parameters of a coaster and investigate its safety and thrill: hill height, loop radius and speed
The velocity and acceleration vectors are drawn as an object circles at steady speed
Spin a turntable with a disk on it; find the speed at which friction can no longer hold it
Drive a car on a banked curve; find the speed at which no friction is needed (banked up)
Second banked-road case with the friction direction reversed
Solve a net-inward-force problem with adjustable radius, speed and mass
Fly a drone around a circular tunnel and inspect velocity and acceleration vectors
Release a cart from a chosen height into a vertical loop; find the minimum height to stay on track
Design the spinning barrel: modify its parameters so the riders stay pinned to the wall when the floor drops
F = Gm₁m₂/r²: inverse-square law and Newton’s third law pair.
Move two masses closer or farther and see how the gravitational force vector scales
Jump on different planets; compare jump height and hang time against surface gravity
Set the masses, positions and velocities of up to four bodies and watch their gravitational orbits unfold.
Investigate elliptical orbits and Kepler's laws by changing the satellite's starting speed and position
Place any number of masses, give them initial velocities and watch the gravitational interactions, slingshots, captures and ejections
Change two masses and their separation; read the gravitational attraction between them
F = Gm₁m₂/r²: inverse-square law and Newton’s third law pair.
Move two masses closer or farther and see how the gravitational force vector scales
Change the masses and the separation and observe the gravitational force values
Set the masses, positions and velocities of up to four bodies and watch their gravitational orbits unfold.
Place any number of masses, give them initial velocities and watch the gravitational interactions, slingshots, captures and ejections
Planet orbiting a sun: set initial speed, distance and masses; see elliptical orbit and equal-area sweeps
Investigate elliptical orbits and Kepler's laws by changing the satellite's starting speed and position
Change two masses and their separation; read the gravitational attraction between them
Change orbital radius and read the period; verify T^2 proportional to r^3
Increase a cannonball's launch speed from a mountain until it orbits Earth
Vary Earth's orbital speed around the Sun and see circular, elliptical or escape trajectories
Drag two large masses and change them; read the gravitational force on each and watch the force arrows.
Field strength falls as 1/r²; an orbit needs v² = GM/r.
Explore how g varies with location around the globe and with altitude
Change orbital radius and read the period; verify T^2 proportional to r^3
Increase a cannonball's launch speed from a mountain until it orbits Earth
Compare the value of g on other planets from each planet's mass and radius
Planet orbiting a sun: set initial speed, distance and masses; see elliptical orbit and equal-area sweeps
Jump on different planets; compare jump height and hang time against surface gravity
Vary Earth's orbital speed around the Sun and see circular, elliptical or escape trajectories
Drag a planet’s orbit and watch equal areas sweep in equal times; compare T² with a³.
Hop on the scales on other planets and see how your weight changes with location
Fly a probe past a moving planet to gain speed via gravitational assist
Adjust eccentricity of a planet's orbit and watch the Sun sit at a focus of the ellipse
Watch a planet sweep equal areas in equal times as orbital speed changes
Escape speed depends on the planet's mass and radius.
Orbits around a point mass — change masses and distance, watch period and shape respond.
A ball lifted through height contours beside a charge moved through equipotential rings; drag either and change its size
Energy flows from hot to cold until thermal equilibrium; equal energy gives unequal ΔT when c differs.
Mix ice and water at chosen masses and temperatures; find the final temperature
Heat one end of a metal rod and watch conduction spread along it
Heat a gas and watch molecules speed up; relate temperature to KE
Calibrate a liquid-in-glass thermometer between fixed points
Three benches: conduction along a metal bar to steady state, convection rolls in a heated fluid layer, and radiation
Invisible molecules collide with a smoke particle from every side; the imbalance at any instant moves it
Cool a gas at constant volume and extrapolate the P-T line to absolute zero
Measure absolute zero by plotting pressure against temperature for a gas
Heat a liquid from below and watch convection currents form
Heat ice to steam and see the temperature plateau at each phase change
Pressure falls linearly with temperature and the line meets zero pressure at -273 °C, absolute zero.
Measure absolute zero by plotting pressure against temperature for a gas
Calibrate a liquid-in-glass thermometer between fixed points
Temperature stays constant during each phase change because the energy goes into latent heat, and boiling needs more than melting.
Heat and cool bricks, water and iron; show the energy symbols as they transfer.
Mix ice and water at chosen masses and temperatures; find the final temperature
Heat or cool neon, argon, oxygen or water and watch the particles melt, boil and freeze.
Cool water below 0 C without freezing, then nucleate it; observe latent heat release
Heat a gas and watch molecules speed up; relate temperature to KE
Vary initial temperature and ambient temperature; watch the exponential cooling curve of a hot object
Vary P, V, n and T of an ideal gas and watch the equation of state balance
Cool a gas at constant volume and extrapolate the P-T line to absolute zero
Measure absolute zero by plotting pressure against temperature for a gas
pV = nRT: each pair of variables scales exactly as the equation predicts.
Vary P, V, n and T of an ideal gas and watch the equation of state balance
A gas cylinder with piston, thermometer, pressure gauge, volume and number of moles; set an initial state and change it
Cool a gas at constant volume and extrapolate the P-T line to absolute zero
A simpler gas box: change the number of particles, heat them, and read the pressure.
Measure absolute zero by plotting pressure against temperature for a gas
Pressure comes from momentum change at the walls; ½m⟨c²⟩ = 3/2 kT so lighter particles move faster at the same T.
Heat a gas and watch molecules speed up; relate temperature to KE
Watch a pollen grain jostled by invisible gas molecules; change temperature
A gas cylinder with piston, thermometer, pressure gauge, volume and number of moles; set an initial state and change it
Two gases separated by a divider — remove it and watch them mix by random motion.
Invisible molecules collide with a smoke particle from every side; the imbalance at any instant moves it
Release gas molecules on one side of a barrier and watch diffusion
During a phase change energy goes into potential energy (bonds), not kinetic — so T is constant.
Look inside the box: particle speeds, collisions with the walls, and the speed distribution.
Drag two atoms apart and watch the Lennard-Jones force and potential-energy curves change with separation and atom pair.
Heat a gas at constant volume and watch pressure rise with no work done
Compress a gas with no heat exchange; see temperature rise on the adiabat
Run a gas around a closed PV cycle and read net work from the enclosed area
Expand a gas at constant pressure; compute work from the PV area
Compress a gas at constant temperature and trace the isotherm on a PV diagram
Track temperature change during an adiabatic compression or expansion
Rub two books together and watch the atoms at the surfaces jiggle faster as the thermometer rises.
Work done equals pΔV, the rectangle under the isobar.
Heat a gas at constant volume and watch pressure rise with no work done
Compress a gas at constant temperature and trace the isotherm on a PV diagram
Compress a gas with no heat exchange; see temperature rise on the adiabat
Run a gas around a closed PV cycle and read net work from the enclosed area
Pump particles into a box; hold one variable fixed and change the others.
Watch intake, compression, power and exhaust strokes of a 4-stroke engine
Track temperature change during an adiabatic compression or expansion
Set mass, spring constant and amplitude; watch x, v, a graphs and the energy exchange of a block on a spring
Run uniform circular motion beside its projection to see SHM as a shadow of circular motion
SHM related to uniform circular motion with x-t, v-t and a-t graphs toggled by checkbox
Hang a mass on a spring, set it bouncing and read the period, energy bars and graph.
Set length and amplitude of a simple pendulum; read the period and compare with the formula
Link SHM, uniform circular motion and a transverse wave side by side with sliders and checkboxes
Mass on a horizontal spring: set initial displacement, mass and k; step through motion with x, v, a graphs
Quiz: match or interpret displacement/velocity/acceleration graphs of an oscillator
Step-by-step tutorial on SHM with embedded interactive panels (Next/Back navigation)
Compare two SHM oscillators / waves with an adjustable phase shift between them
A marker on a turntable oscillates one cycle per turn and traces a sine wave, with 3D viewing
Place a mass on a spring, or different masses on two springs, press Start and measure the height over time
A mass on a spring bounces while displacement is plotted against time and energy shifts between kinetic and potential
Change the length and the mass, time the swings, and track the energy exchange through each cycle
Swing a pendulum and watch PE convert to KE and back through the cycle
Drop an extra mass onto an oscillating mass; see the change in amplitude and period
Timed mass-spring oscillator for lab: change mass and k and measure the period
Set length, mass and release angle of a pendulum; step through a worked period and speed problem
Vertical mass on a spring; student sets bob mass, spring constant, damping, rest length and gravity and reads period/frequency and decay in real time
Pendulum bob; set length, mass, gravity, damping and initial angle, read period and frequency, and push the amplitude to break the small-angle approximation
Mass on a frictionless horizontal surface tied to a wall by a spring; drag the mass to set amplitude and set mass, spring constant, damping and rest length
Swing a pendulum; vary length, mass, gravity and amplitude, with a period timer and energy graph.
Hang masses on springs, measure the stretch with the ruler and time the period with the stopwatch.
Drop a second mass onto an oscillating spring-mass at equilibrium or max displacement; compare amplitude/period changes
Simple pendulum: adjust length, initial angle and g; examine forces, acceleration, velocity and energy
Orange balls each in SHM; guess the shape of the overall path (optical illusion)
Pendulum-wave animation in a 2D array of pendulums
Step through a vibrating mass on a vertical spring problem with hints and feedback
A slider each for amplitude, frequency and phase; isolate the effect of one at a time on a sine curve
A point walks round the unit circle while its coordinates are plotted, showing where sine and cosine waves come from
Draggable angle on the unit circle; choose the function, rotation speed, initial angle, amplitude A, angular frequency ω and phase φ; see A·sin(ωθ+φ) plotted
T = 2π√(m/k); amplitude does not change the period.
Set mass, spring constant and amplitude; watch x, v, a graphs and the energy exchange of a block on a spring
Mass oscillating on a vertical spring with live KE / GPE / EPE bar graphs; adjust mass and spring constant
Vertical mass on a spring; student sets bob mass, spring constant, damping, rest length and gravity and reads period/frequency and decay in real time
A mass on a spring bounces while displacement is plotted against time and energy shifts between kinetic and potential
Mass on a horizontal spring: set initial displacement, mass and k; step through motion with x, v, a graphs
Place a mass on a spring, or different masses on two springs, press Start and measure the height over time
Run uniform circular motion beside its projection to see SHM as a shadow of circular motion
Timed mass-spring oscillator for lab: change mass and k and measure the period
Set length and amplitude of a simple pendulum; read the period and compare with the formula
Set length, mass and release angle of a pendulum; step through a worked period and speed problem
Pendulum bob; set length, mass, gravity, damping and initial angle, read period and frequency, and push the amplitude to break the small-angle approximation
Mass on a frictionless horizontal surface tied to a wall by a spring; drag the mass to set amplitude and set mass, spring constant, damping and rest length
Swing a pendulum; vary length, mass, gravity and amplitude, with a period timer and energy graph.
Amplitude builds largest when the driving frequency matches the natural frequency.
Add friction to a swinging pendulum and watch the amplitude decay cycle by cycle.
Vertical mass on a spring; student sets bob mass, spring constant, damping, rest length and gravity and reads period/frequency and decay in real time
Damped spring oscillations — tune the damping slider and compare decay envelopes.
Drive an oscillator at a frequency you choose and plot the amplitude response as you sweep through resonance
A standing wave forms in an air column; change its length to hear and see the resonant frequency shift
Pendulum bob; set length, mass, gravity, damping and initial angle, read period and frequency, and push the amplitude to break the small-angle approximation
Mass on a frictionless horizontal surface tied to a wall by a spring; drag the mass to set amplitude and set mass, spring constant, damping and rest length
Several stations broadcast at once; tune the LC circuit and only the station matching its natural frequency comes through
Two identical pendulums are coupled and energy sloshes between them; find the two modes in which it does not
A solid metal plate swinging between magnet poles stops in a couple of swings while a slotted plate keeps going; switch plate types
E ∝ 1/r² from a point charge; field lines run from + to −, perpendicular to equipotentials.
Place positive and negative charges; see field lines and field vectors
Drag source charges onto the workspace, see the lines of force, and tap any point for the field vector; 3D view
Electric field inside and outside a charged spherical shell
Drag positive or negative charges onto the space and observe the electric field lines
Drag +1 nC / -1 nC point charges; see field lines and the electric potential map update
Field lines traced from the computed field; drag the test charge around and flip its sign to see it pushed along the lines
Probe a 3D field and plot equipotential lines around configured charges
Add point charges and an external field; watch each charge accelerate along the field.
Place fixed positive and negative charges to steer a moving puck into the goal using electrostatic force.
Place charges to steer a puck around obstacles and into the goal
Place a charge inside a conducting cage and see the field cancel inside
C = ε₀A/d, E = V/d between the plates, energy = ½QV.
Launch a charge into a uniform electric field and watch the parabolic deflection
Electric field between two parallel charged metal plates
Simplified Millikan oil-drop: adjust plate voltage to balance a charged droplet and deduce its charge
Hang a charged ball on a string in a uniform field; find the deflection angle
Shoot a charged particle into a uniform electric field; adjust charge, mass, speed and field; see parabolic path
An electron gun, accelerating anode and deflecting plates; drive the glowing spot around the screen
Fire an electron and a photon into the same electric and magnetic fields and see which one bends
Electric field of an infinite charged sheet
Suspend oil drops between charged plates to find the electron charge
Equipotential surfaces between capacitor plates
Insert a dielectric and vary plate area/gap; read field, capacitance and stored energy
Balance electric and magnetic deflection of a cathode ray, as J.J. Thomson did
Line up rows of + and − charges to build a nearly uniform field and probe it.
Add point charges and an external field; watch each charge accelerate along the field.
Place charges to steer a puck around obstacles and into the goal
F = Qq/(4πε₀r²): inverse-square and equal-and-opposite on both charges.
Three-charge Coulomb problem: find the net force on each charge
Two charged objects: set charges and positions; see Coulomb force vectors and magnitudes
Coulomb's law for lab: collect force-distance data and fit the inverse square
Four-charge Coulomb problem in a square arrangement
Three charged objects: set charges and positions; see each pairwise force and the resultant
Change the charge values and the separation and observe the force
Place charges anywhere on the canvas and drag them around while the force arrows resize in real time
Change two charges and their separation; read the Coulomb force
Place fixed positive and negative charges to steer a moving puck into the goal using electrostatic force.
E ∝ 1/r² from a point charge; field lines run from + to −, perpendicular to equipotentials.
Electric field inside and outside a charged spherical shell
Two concentric charged shells: see how field strength and potential vary inside the inner shell, between the shells and outside
Drag source charges onto the workspace, see the lines of force, and tap any point for the field vector; 3D view
Drag +1 nC / -1 nC point charges; see field lines and the electric potential map update
Two charges: set charge and position; plot equipotential lines and electric field around them
Place positive and negative charges; see field lines and field vectors
Probe a 3D field and plot equipotential lines around configured charges
E ∝ 1/r² from a point charge; field lines run from + to −, perpendicular to equipotentials.
Place two charges on the conductive paper, tap Start and watch the potential landscape form
Two concentric charged shells: see how field strength and potential vary inside the inner shell, between the shells and outside
Equipotential surfaces around two point charges
Two charges: set charge and position; plot equipotential lines and electric field around them
A ball lifted through height contours beside a charge moved through equipotential rings; drag either and change its size
Drag +1 nC / -1 nC point charges; see field lines and the electric potential map update
Probe a 3D field and plot equipotential lines around configured charges
Equipotential surfaces between capacitor plates
Equipotentials between a point charge and a plate
Equipotentials between a point charge and a conducting shell
C = ε₀A/d, E = V/d between the plates, energy = ½QV.
Connect capacitors in parallel and read the equivalent capacitance
Connect capacitors in series and read the equivalent capacitance
Construct capacitor combinations and compute equivalent C
Practice finding equivalent capacitance of random networks
Change the plate size, separation and dielectric of a capacitor; measure capacitance, charge, stored energy and field.
RC charging: adjust voltage, resistance, plate area and separation; open/close switch and watch charge build
See the current flow, voltage and current readings in a simple RC circuit as the capacitor charges and discharges
Introduction to a capacitor: charge plates and see Q, V and C
Insert a dielectric and vary plate area/gap; read field, capacitance and stored energy
Charge and discharge a capacitor through a resistor; read current and charge curves
Charge and discharge an RC circuit; read the exponential curve and time constant
Drive a tiny electrostatic motor from a charged capacitor
C = ε₀A/d, E = V/d between the plates, energy = ½QV.
Insert a dielectric and vary plate area/gap; read field, capacitance and stored energy
Introduction to a capacitor: charge plates and see Q, V and C
Change the plate size, separation and dielectric of a capacitor; measure capacitance, charge, stored energy and field.
Construct capacitor combinations and compute equivalent C
Connect capacitors in parallel and read the equivalent capacitance
Connect capacitors in series and read the equivalent capacitance
Practice finding equivalent capacitance of random networks
Both curves are exponential with time constant RC.
Charge and discharge a capacitor through a resistor; read current and charge curves
See the current flow, voltage and current readings in a simple RC circuit as the capacitor charges and discharges
RC charging: adjust voltage, resistance, plate area and separation; open/close switch and watch charge build
Feed a square wave into an RC circuit and view the charging/discharging output
Build an RC circuit, charge the capacitor and watch the current and voltage decay.
Drive an RC circuit from AC and relate the time constant to the output
Neon-lamp relaxation oscillator: a practical RC timing application
Field lines leave N and enter S; the compass aligns with the local field direction.
Map the field lines around a bar magnet with a probe
Map the field between poles of a U-shaped magnet
Switch on a current and see a compass deflect, as Oersted did
Compare a bar magnet with a coil carrying current; change loops and current and probe B.
Drag a compass needle through the space around a bar magnet and observe the magnetic field
Drag, flip and orient six bar magnets and observe their attractions, repulsions and the surrounding field
Compasses sit above and below a current-carrying wire; they point in opposite directions because the field wraps round the wire
Move a compass through a field and see it align with field lines
Probe the axial field inside a solenoid; vary turns and current
Map the field inside and around a solenoid
Bring two bar magnets together and feel attraction and repulsion
Interaction between horseshoe magnets
F = BIL sin θ: the force is largest when the wire is perpendicular to the field and zero when parallel.
Adjust the current, conductor length, field strength and orientation and see the force on the wire
DC motor: adjust voltage, field strength and number of turns; see force on the coil and rotation
Run a DC motor; see the force couple and commutator reversal
Run parallel currents in two wires; see attraction or repulsion
Rotate a hand model in 3D together with the field, current and force vectors until the rule makes sense
A current-carrying wire in a magnetic field; vary the angle between current and field and watch the force vector
The forces on each side of a rectangular coil in a uniform field are isolated in 3D; rotate the coil while watching the arrows
A moving-coil galvanometer in 3D: rotate the view to see the coil in the field of the curved pole pieces and watch the pointer settle
Explore the coil, magnet and spring in 3D and see how the motor effect turns a current of a few microamps into a deflection
Follow the current path through the coil, the forces on each side, and the moment the split ring reverses the connection
Add coils around the armature and compare the torque trace with the single-coil version
Fire a railgun: current through rails and armature produces magnetic thrust
r = mv / (qB): faster charges make bigger circles and stronger fields make smaller ones.
Pass current through a slab in a B field and read the Hall voltage
Balance electric and magnetic deflection of a cathode ray, as J.J. Thomson did
Fire ions down the chamber through the charge accelerator, velocity selector and detector; analyse each section
Launch an electron at an angle to a B field and see its helical path
Thomson e/m experiment: balance electric and magnetic deflection of an electron beam and compute e/m
Shoot a charged particle into a uniform magnetic field; vary q, m, v and B; see the circular path and radius
3D charged particle in a magnetic field with velocity components along and across B; see helical motion
An electron gun, accelerating anode and deflecting plates; drive the glowing spot around the screen
Fire an electron and a photon into the same electric and magnetic fields and see which one bends
Bend an electron beam in a known B field to measure e/m
A current loop makes the same field shape as a bar magnet; more loops or current → stronger B.
Map the field inside and around a solenoid
Probe the axial field inside a solenoid; vary turns and current
Switch on a current and see a compass deflect, as Oersted did
Run parallel currents in two wires; see attraction or repulsion
Field lines are plotted around a straight wire; probe the strength at any distance
Build an electromagnet and explore what increases the strength of its magnetic field
A solenoid is built one circular loop at a time in 3D so you can watch the field evolve
Compasses sit above and below a current-carrying wire; they point in opposite directions because the field wraps round the wire
Two parallel wires each produce a circular field; find the neutral point and see how it shifts when the currents change
Operate an electric bell driven by an electromagnet
E.m.f. ∝ rate of change of flux linkage; no change → no e.m.f.; direction reverses when motion reverses.
Move a magnet through a coil; read induced emf versus rate of flux change
Drop a magnet through a conducting tube; see the opposing induced current
Tilt a loop in a field and read the magnetic flux
Spin a coil in a magnetic field and watch the sinusoidal emf
A flux–time graph and the e.m.f. it produces are drawn side by side in real time
Move a bar magnet through a coil; see the induced current direction and size
A coil turns between magnet poles and the induced e.m.f. is drawn against angle; slip rings keep each brush on the same end of the coil
Push a bar magnet into a coil and the galvanometer needle kicks; hold it still and the needle falls back to zero
A magnet falls through a coil under gravity and the induced e.m.f. is graphed in real time
Triangles, circles, squares and rectangles cross the same field boundary and their e.m.f. traces are plotted for comparison
Add a commutator to a generator and see the rectified DC output
Move a conductor through a magnetic field and watch eddy currents form
Switch on a coil and watch an aluminium ring jump off
Pickup coils, electromagnets, transformers and a generator — full induction playground.
Spin a magnet near a coil with a water wheel and watch the induced current alternate.
The same coil and magnet as the AC machine, but a split-ring commutator replaces the slip rings
Several coils on one shaft at equal spacings, each with its own commutator segments; the output follows whichever coil is nearest its peak
Turn the coil in the field and watch the e.m.f. trace build and collapse while the split-ring commutator keeps the output one way
Add coils to the armature and plot the combined output; the ripple smooths towards a steady DC level
A water-cooled coil produces an alternating field that drives eddy currents inside the metal charge until it melts
A coil beneath the glass produces an alternating field, and eddy currents in the pan base do the heating
A conducting sheet moves past a magnet; see the eddy currents induced in it and the retarding force with nothing touching
A solid metal plate swinging between magnet poles stops in a couple of swings while a slotted plate keeps going; switch plate types
Change turns ratio of a transformer; read primary and secondary voltages
V = V₀ sin ωt; I and V peak together in a resistive circuit; r.m.s. = peak/√2.
Spin a coil in a magnetic field and watch the sinusoidal emf
Draggable angle on the unit circle; choose the function, rotation speed, initial angle, amplitude A, angular frequency ω and phase φ; see A·sin(ωθ+φ) plotted
Spin a magnet near a coil with a water wheel and watch the induced current alternate.
A coil turns between magnet poles and the induced e.m.f. is drawn against angle; slip rings keep each brush on the same end of the coil
Assemble resistors, capacitors and inductors into AC circuits and watch the voltage and current traces with their phase relationship
Add a commutator to a generator and see the rectified DC output
Build AC and DC circuits from batteries, AC sources, resistors, capacitors and inductors, measured with realistic meters only.
Several stations broadcast at once; tune the LC circuit and only the station matching its natural frequency comes through
The wire expands as it heats, the fine thread takes up the slack and the pointer swings; works on AC and DC alike
Change turns ratio of a transformer; read primary and secondary voltages
Build AC circuits from sources, R, L and C; measure phase and amplitude
Add a commutator to a generator and see the rectified DC output
Rectify an AC supply with a diode, then add a capacitor across the load to smooth it.
Stopping potential depends on wavelength, not intensity, and no current flows below the threshold frequency.
Shine light of chosen wavelength and intensity on a metal target; read the photocurrent and find the stopping voltage.
Slide the temperature of a glowing body and watch its spectrum move across the EM bands.
Stopping potential depends on wavelength, not intensity, and no current flows below the threshold frequency.
Shine light on a metal; change the intensity and the frequency and observe the emitted electrons
Slide the temperature and watch the emitted spectrum — intensity and peak wavelength.
Single particles arrive as dots but accumulate into a wave pattern: wave–particle duality.
Scatter electrons from a nickel crystal and find the diffraction peak
Send photons one at a time through a double slit and watch fringes build up
A de Broglie wave is wrapped around each Bohr orbit; only orbits fitting a whole number of wavelengths survive
The electron wave wraps around the nucleus; test which radii allow it to close on itself
Particles pass through a double slit one at a time and the hits accumulate in 3D until a pattern emerges
Build a wave packet and see how particle-like localisation trades off with wavelength spread
Discrete levels → discrete photon energies hf = E₂ − E₁ → line spectra.
Hydrogen energy-level diagram: pick transitions and see emitted/absorbed photon energies and spectral lines
View emission spectra of elements; relate lines to energy level transitions
Sweep accelerating voltage and see current dips at quantised energies
Fire electrons at atoms in a gas tube; watch them excite the atoms and read the emitted lines on the spectrometer.
A de Broglie wave is wrapped around each Bohr orbit; only orbits fitting a whole number of wavelengths survive
Excite the atom and watch electrons drop between levels, producing the matching spectral line each time
Run a spectrometer on a gas discharge tube and read line wavelengths
Click between hydrogen energy levels and see the emitted photon wavelength
The fused nucleus has less mass than its parts, and the mass defect appears as energy.
Assemble nuclei and read off stability; follow decays on the nuclide chart.
Fire a neutron at U-235 and see fission fragments and chain reaction
Fire a neutron at uranium-235 to split it, start a chain reaction, then control it with rods in a reactor.
Control rods and moderator in a fission reactor; manage the chain reaction
Confine a plasma in a tokamak fusion reactor
Watch a polonium-211 nucleus, or a custom one, emit an alpha particle; the timing chart shows when each decay happens.
Measure how much carbon-14 or uranium-238 is left in rocks, bones and other objects and read off their age from the decay curve.
Watch hydrogen-3 or carbon-14 nuclei undergo beta decay, emitting an electron and an antineutrino, with half-life timing.
Watch an alpha particle tunnel out of a heavy nucleus
Run coin tosses in bulk and watch the experimental fraction close in on the theoretical value
Watch a neutron become a proton with beta and antineutrino emission
See an excited nucleus de-excite by emitting a gamma photon
Add protons and neutrons to a nucleus and watch which decays it undergoes.
Electrons boil off a heated filament, accelerate across a large p.d. and hit a tungsten target to produce X-rays
The continuous hump and the sharp spikes of an X-ray spectrum are separated; change the voltage or the target material
Intensity falls as 1 divided by distance squared.
Match a star’s surface temperature to its spectrum — Sirius, the Sun, a red giant.
Change the temperature of a black body and watch the spectrum shift (Wien, Stefan)
λ_peak T = 2.9×10⁻³ m K; luminosity L = 4πr²σT⁴ links T, r and brightness.
Change the temperature of a black body and watch the spectrum shift (Wien, Stefan)
Plot the full blackbody spectrum at any temperature and watch the peak slide towards shorter wavelengths
The best-fit line balances the squared vertical distances — worst and best lines bracket the true gradient.
Drop data points with error bars; fit a line or polynomial and watch the residuals.
Fire many projectiles from one launcher and analyse the landing positions with histograms, the mean and the spread.
Timed mass-spring oscillator for lab: change mass and k and measure the period
Coulomb's law for lab: collect force-distance data and fit the inverse square
Change m or c and the drawn line moves immediately, linking the equation to the graph
Each simulation stays the property of its source and is credited on the card inside the lesson. Back to the A Level Physics course →