An object with a mass of #12 kg# is moving at #9 m/s# over a surface with a kinetic friction coefficient of #3 #. How much power will it take to accelerate the object at #3 m/s^2?

1 Answer
Feb 13, 2018

The power is #=3499.2W#

Explanation:

The mass of the object is #m=12kg#

The initial velocity is #u=9ms^-1#

The acceleration is #a=3ms^-2#

The coefficient of kinetic friction is

#mu_k=F_r/N=3#

#F_r=mu_kN#

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

The normal force is

#N=mg=12g#

In order to accelerate the object, Apply Newton's Second Law of Motion

#F-F_r=ma#

#F=F_r+ma=3*12g+12*3=388.8N#

The power is

#P=Fv=388.8*9=3499.2W#