Hooke's Law (Cambridge O Level Physics)

• Hooke’s law states that:

The extension of a spring is proportional to the applied force

• Where:
  • F is the force applied
  • k is the spring constant
  • x is the extension of the spring

• The spring constant is the force per unit extension
  • The units are N/m
  • The spring constant is a measure of how stiff the spring is

• Directly proportional means that as the force is increased, the extension increases 
  • If the force is doubled, then the extension will double
  • If the force is halved, then the extension will also halve
• The limit of proportionality is the point beyond which the relationship between force and extension is no longer directly proportional 
  • This limit varies according to the material

Hooke's Law states that a force applied to a spring will cause it to extend by an amount proportional to the force