Question

Force shown acts for $2$ seconds. Find out work done by force $F$ on $10$ kg in $3$ seconds.

• A. 30 J
• B. 20 J
• C. 50 J
• D. 60 J

Answer 1

Answer: (B)

20 J

Work done,
$W=Fd$
Displacement $d$ is given by,
$d=\frac{1}{2}a{t}^2$
$F=ma$
$10=10a$, $a=1m/s^2$
$d=\frac{1}{2}\left(1\right){\left(2\right)}^2=2m$
$W=10\times 2=20J$