🌟 Flashcard Summary: Work Done & Elastic Potential Energy

Work is done whenever a force causes an object to move in the direction of the force. When this happens, energy is transferred from one form to another.

• Stretching a material → e.g. chemical energy in muscles → elastic potential energy
• Pushing a vehicle → chemical energy in muscles → kinetic energy of the moving vehicle
• A force that stretches or compresses a spring → energy stored in the spring

Elastic potential energy (also called elastic strain energy) is the energy stored when a spring or elastic material is stretched or compressed.

🔢 Elastic Potential Energy Equation

Elastic potential energy stored in a spring:

E = ½ k e²

• E = elastic potential energy (J)
• k = spring constant (N/m) — how stiff the spring is
• e = extension or compression (m)

📏 Units to Remember

• Energy → joules (J)
• Spring constant → newtons per metre (N/m)
• Extension → metres (m)

Exam tip: If extension is given in centimetres, always convert to metres before using the equation.

Key Physics GCSE Takeaways

• Work done means energy is transferred
• Stretching or compressing stores energy elastically in the material
• Stiffer springs (larger k) store more energy
• Doubling the extension quadruples the energy stored