An object with a mass of #5 kg# is on a surface with a kinetic friction coefficient of # 3 #. How much force is necessary to accelerate the object horizontally at #7 m/s^2#?

1 Answer
Jul 11, 2017

The force is #=182N#

Explanation:

The coefficient of friction is

#mu_k=F_r/N#

The frictional force is #F_r#

The normal force is #N=mg#

The net force on the object is #=F#

According to Newton's Second Law

#F-F_r=ma#

#F-mu_kN=ma#

#F=mu_kmg+ma=m(mu_kg+a)#

#mu_k=3#

#a=7ms^-2#

#m=5kg#

Therefore,

#F=5(3*9.8+7)=182N#