The spring is initially in an equilibrium condition. Initially it is stretched by length l and the work done is U 1 . Again, it is stretched by length 2 7 l , when the work done is U 2 , the val

Question

The spring is initially in an equilibrium condition. Initially it is stretched by length l and the work done is U 1 ​ . Again, it is stretched by length 2 7 l ​ , when the work done is U 2 ​ , the value of U 2 ​ is

TestHub · Accepted Answer

The work done in stretching a spring by a distance $x$ from its equilibrium position is given by $U = \frac{1}{2} k x^{2}$ .

For the first case, the spring is stretched by a length $l$ .

$U_{1} = \frac{1}{2} k l^{2}$

For the second case, the spring is stretched by a length $\frac{7 l}{2}$ from its equilibrium position.

$U_{2} = \frac{1}{2} k (\frac{7 l}{2})^{2}$

$U_{2} = \frac{49}{4} (\frac{1}{2} k l^{2})$

$U_{2} = \frac{49}{4} U_{1}$

Answer: $\frac{49}{4} U_{1}$

Physics - W.E.P. Question with Solution | TestHub

Options:

Doubts & Discussion