Question

A spring of force constant $k$ is cut in two parts at its one-third length. When both the parts have same elongation, the work done in the two parts will be (Spring constant of a spring is inversely proportional to length of spring)

• A. Equal to both
• B. Greater for the longer part
• C. Greater for the shorter part
• D. Data insufficient

Answer 1

The correct option is C Greater for the shorter part

$k\alpha \frac{1}{l}$
l of shorter part is less, therefore value of k is more
$W=\frac{1}{2}k{x}^2$
$\therefore W_{\text{shorter part}}$ will be more.