-->

Work, Energy And Power

Question

Two springs of spring constants k₁ and k₂ are stretched by the same force. First spring undergoes more extension than the second one. In which of the two springs, energy stored will be more?

Solution

According to Hook's law we have,
F = kx
$rightwards double arrow$ k = F/x
Energy stored in stretched spring is,
$U equals 1 half k x squared equals 1 half F over x x squared equals 1 half F x$
Hence for the same force applied, the energy stored in spring is directly proportional to extension.
Therefore, energy stored in first spring will be greater than the second spring.