\[(a)\;\frac{8}{3}\;J\quad (b)\;\frac{19}{5}\;J \quad (c)\; \frac{5}{19}\;J \quad (d)\;\frac{3}{8}\;J\]

$s=\large\frac{1}{3}$$t^2=>\large\frac{ds}{dt}=\frac{2}{3}$$t$

acceleration $=a=\large\frac{d^2s}{dt^2}$

$\qquad=\large\frac{2}{3}$$m/s^2$

Force $=m \times a$

$ \qquad=3 \times \large\frac{2}{3}$$=2N$

$ds=\large\frac{2}{3}$$tdt$

Work done $= \int F ds$

$W=F \int \limits_0^t \large\frac{2}{3} $$t dt$

$\quad=2 \times \large\frac{2}{3} $$ \times \large \frac{t^2}{2} \bigg|_0^2$

$\quad=\large\frac{4}{3} \times \frac{4}{2}$

$\quad=\large\frac{8}{3}$$\;J$

Hence a is the correct answer.

Ask Question

Tag:MathPhyChemBioOther

Take Test

...