Question

A block of mass '$m$' is attached to a spring in natural length of spring constant '$k$'. The other end $A$ of the spring is moved with a constant velocity $v$ away from the block. Find the maximum extension in the spring.

• A. $\frac{1}{4}\sqrt{\frac{m{v}^2}{k}}$
• B. $\sqrt{\frac{m{v}^2}{k}}$
• C. $\frac{1}{2}\sqrt{\frac{m{v}^2}{k}}$
• D. $2\sqrt{\frac{m{v}^2}{k}}$

Answer 1

Answer: (B)

$\sqrt{\frac{m{v}^2}{k}}$

Potential energy stored in the spring will be equal to the kinetic energy.
$\frac{1}{2}k{x}^2=\frac{1}{2}m{v}^2$
$x=\sqrt{\frac{m{v}^2}{k}}$