Calculating Work Done in Stretching (WJEC GCSE Physics)

• When a spring is stretched by a force work is done by the spring
• The work done in stretching a spring is equal to the elastic energy stored in the spring

Work Done in Stretching a Spring

Work is done on a spring when it is stretched

• Work done is calculated using the equation:

• Where:
  • W  = work done by the spring or elastic potential energy (J)
  • F = force applied to stretch the spring (N)
  • x = extension of the spring (m)
• This is only valid for springs not stretched beyond their limit of proportionality 

Calculating Work Done from the Force-Extension Graph

• Work done is calculated from the area under a force-extension graph
• The area under the graph forms a triangle shape
  • Where the area of a triangle is 
• So, the work done = area = 

Area Under a Force-Extension Graph

The area under the force-extension graph is a triangle. Calculating the area of the triangle gives the work done by the spring when stretched