Question

If the potential energy of a spring is V on stretching it by 2 cm then its potential energy when it is stretched by 10 cm will be

• A. V/25
• B. 5 V
• C. V/5
• D. 25 V

Answer 1

The correct option is D 25 V

Potential Energy $\propto x^2$

Therefore

$\frac{V_1}{V_2}=\frac{(x_1{)}^2}{(x_2{)}^2}$

Here $V_1=V$

$x_1=4$

$x_2=10$

So $\frac{V}{V_2}=\frac{(2{)}^2}{(10{)}^2}$

$\frac{V}{V_2}=\frac{4}{100}$

$\frac{V}{V_2}=\frac{1}{25}$

$V_2=25V$

Hence the correct option is (D).