Solution:
Work done in stretching a string to obtain an extension I,
Similarly, work done is stretching a string to obtain extension
Now, work done in second stretching,
A string of length L and force constant k is stretched to obtain extension l. It is further stretched to obtain
extension l1. The work done in second stretching is [MHT CET 2014]
Work done in stretching a string to obtain an extension I,
Similarly, work done is stretching a string to obtain extension
Now, work done in second stretching,