Question

A block of mass m slips down an inclined plane as shown in the figure it presses a spring lying at the bottom. If the length of the spring $l>>h$ and spring constant is $K$ the compression in the spring will be:

• A. $\sqrt{\frac{mgh}{k}}$
• B. $\sqrt{\frac{2mgh}{k}}$
• C. $\sqrt{\frac{gh}{mk}}$
• D. $\sqrt{\frac{2gh}{mk}}$

Answer 1

The correct option is B $\sqrt{\frac{2mgh}{k}}$

From conservation of energy,
$\frac{1}{2}k{x}^2=mgh\Rightarrow x=\sqrt{\frac{2mgh}{k}}$