9702 · 12.2
Centripetal acceleration — FAQ
Frequently asked questions for 9702 Centripetal acceleration. Direct answers first, then deeper explanation — then practise with marking.
Why does an object moving at constant speed in a circle still accelerate?
It accelerates because its velocity is a vector, and even if its magnitude (speed) is constant, its direction is continuously changing. This change in direction constitutes acceleration.
What is the key difference between centripetal acceleration and linear acceleration?
Linear acceleration primarily causes a change in speed (magnitude of velocity), while centripetal acceleration primarily causes a change in direction of velocity, maintaining circular motion.
Can an object moving in a circle have zero centripetal force?
No, an object in circular motion must have a centripetal force acting on it. If the centripetal force were zero, the object would immediately move in a straight line tangent to its circular path, according to Newton's First Law.