Question

An object with a mass of `6 kg` is moving at `27 m/s` over a surface with a kinetic friction coefficient of `6`. How much power will it take to accelerate the object at #8 m/s^2?

Answer 1

The power is `=10821.6W`

Explanation:

The mass of the object is `m=6kg`

The speed is `u=27ms^-1`

The acceleration is `a=8ms^-2`

The coefficient of kinetic friction is

`mu_k=F_r/N=6`

The normal force is `N=6gN`

The frictional force is `F_r=mu_k xx N=6*6g=36gN`

The force necessary to accelerate the object is `=FN`

The acceleration due to gravity is `g=9.8ms^-2`

According to Newton's Second Law

`F-F_r=ma`

`F=ma+F_r=((6xx8)+(36g))N=400.8N`

The power is

`P=Fxxv=400.8*27=10821.6W`