Elasticity and Hooke's Law

This lesson covers Hooke's law, elastic and plastic deformation, force-extension graphs, and the energy stored in a spring — as required by the Edexcel GCSE Physics specification (1PH0), Topic 1: Key Concepts of Physics. You need to understand the linear relationship between force and extension, interpret force-extension graphs, and calculate elastic potential energy (Higher tier).

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Hooke's Law

Hooke's law states that the extension of a spring is directly proportional to the force applied, provided the limit of proportionality is not exceeded.

$F = kx$F=kx

Where:

• F = force applied (N)
• k = spring constant (N/m)
• x = extension (m)

Key Points