Question

An object with a mass of `15 kg` is moving at `4 m/s` over a surface with a kinetic friction coefficient of `2`. How much power will it take to accelerate the object at `3 m/s^2?`

Answer 1

The power is `=1356J`

Explanation:

The normal reaction is `N=mg=15gN`

The frictional force

`F_r=mu_k.N`

`F_r=2*15g N`

Let the force necessary to accelerate the object be `F`

Then,

`F=F_r+m*a`

`=30g+15*3`

`=339N`

The power is

`P=Fv`

`=339*4`

`=1356W`