Question

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

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

Answer 1

The correct option is A $200$ J

Given that,

Spring constant $k=100$

Mass $m=10kg$

Stretching $x=2m$

We know that,

The work done is

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

$W=\frac{1}{2}\times 100\times 4$

$W=200J$

Hence, the work done is $200J$