Question

A body of mass $6kg$ is under a force of $6N$ which causes displacement in it given by $S=\frac{t^2}{4}m$ where 't' is time. The work done by the force in $2s$ is :

• A. $12J$
• B. $9J$
• C. $6J$
• D. $3J$

Answer 1

The correct option is D $3J$

Workdone $W=F\times 1S=6\left(\frac{t^2}{4}\right)$
at $t=2s$
$W=6\left(\frac{2^2}{4}\right)=6J$