Question

Fig. shows a smooth curved track terminating a smooth horizontal part. A spring of spring constant $400N/m$ is attached at one end to the wedge fixed rigidly with the horizontal part. A $40g$. mass is released from the rest at a height of $4.9m$. on the curved track. Find the maximum compression of the spring:

• A. $17.60cm$
• B. $11.2cm$
• C. $4.9cm$
• D. $9.8cm$

Answer 1

The correct option is D $9.8cm$

From the conservation of energy
$mgh=\frac{1}{2}k{x}^2$
$\Rightarrow x=\sqrt{\frac{2mgh}{k}}=\sqrt{\frac{2\times 0.04\times 9.8\times 4.9}{400}}=9.8cm$