Question

A spring with spring constant k when stretched through 1 cm, the potential energy is U. if it is stretched by 4 cm. the potential energy will be

• A. 4U
• B. 8U
• C. 16U
• D. 2U

Answer 1

The correct option is C 16U

Potential energy $U=\frac{1}{2}k{x}^2$

$\therefore U\propto x^2$ [ if k= constant]

If elongation made $4$ times then potential energy will become $16$ times