Question

Two identical springs of steel and copper are equally stretched. On which more work will have to b done?

Answer 1

Young 's modulus of steel is greater than copper.
Elastic potential energy would be greater for a material with greater Young 's modulus hence the work done is greater.

Answer 2

More work on steel spring.

• Since both are stretched equally, it does not mean that force required to elongate each of them to equal extent, would also be equal.
• Work done is the product of force and distance moved. Stretching both springs to equal amount extent is actually moving them to equal distance.
• The force required to do so will not be same because of difference in properties (elasticity).
• The force required to stretch steel would be relatively more.
• The modulus of elasticity for metals dictates this also known as Young Modulus.