9702 · 6.1
Stress and strain
Every material responds differently when pushed or pulled. Understanding **stress** and **strain** allows us to predict how objects will deform and ultimately how strong they are. This lesson will explore the fundamental concepts of material deformation, from simple stretching to the complex behaviour that leads to breaking, laying the groundwork for engineering and design. This pilot aligns with **Senpai Corner** AS notes (2025–2027) for topic **6.1**.
Need to know
What you need to know
- Stress is symbolised by $\sigma$ (sigma).
- It measures the internal force acting on a material per unit cross-sectional area.
- The SI unit for stress is the Pascal (Pa), where 1 Pa = 1 N m⁻².
- High stress can be achieved with a large force or a very small area, explaining why sharp objects cut easily.
Explanation
Stress and strain
- Stress is symbolised by $\sigma$ (sigma).
- It measures the internal force acting on a material per unit cross-sectional area.
- The SI unit for stress is the Pascal (Pa), where 1 Pa = 1 N m⁻².
- High stress can be achieved with a large force or a very small area, explaining why sharp objects cut easily.