Physics - NLM Question with Solution | TestHub

$u=4m/s, v=0,\mathrm{ }t=2\mathrm{ }\mathrm{s}\mathrm{e}\mathrm{c}$

$v=u+at \Rightarrow \mathrm{ }0=4+2a \Rightarrow \mathrm{ }a=-2{m/s}^2$

$\therefore$$\mathrm{R}\mathrm{e}\mathrm{t}\mathrm{a}\mathrm{r}\mathrm{d}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{ }\mathrm{f}\mathrm{o}\mathrm{r}\mathrm{c}\mathrm{e}=ma=2\times 2=4\mathrm{ }N$

This force opposes the motion. If the same amount of force is applied in forward direction, then the body will move with constant velocity.