Question

A vertical spring of force constant $100N/m$ is attached with a hanging mass of $10kg$. Now an external force is applied on mass so that the spring is stretched (maximum) by additional $2m$. The work by the force $F$ is $(g=10m/s^2)$

• A. $200J$
• B. $400J$
• C. $450J$
• D. $600J$

Answer 1

The correct option is A $200J$

$W=\frac{1}{2}k{x}^2$

$=\frac{1}{2}\times 100\times 2^2$

$=200J$