A small body is projected with a velocity of
20.5 ms−1 on a rough horizontal surface. The coefficient of friction
(μ) between the surface changes with time (
t in
s) as the body moves along the surface. The velocity at the end of
4 s in
ms−1 will be
. (take g=10 ms−2)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1020224/original_5.png)