An object with a mass of #12 kg# is on a surface with a kinetic friction coefficient of # 15 #. How much force is necessary to accelerate the object horizontally at # 4 m/s^2#?

1 Answer
Apr 7, 2017

Answer:

The force is #=1812N#

Explanation:

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The frictional force is

#F_r=mu_k*N#

The normal force is #N=mg#

So,

#F_r=mu_k*mg#

Resolving in the horizontal direction #rarr^+#

We apply Newton's second Law

#F-F_r=ma#

So,

#F=F_r+ma#

#F=mu_kmg+ma#

#=m(mu_kg+a)#

#=12(15*9.8+4)#

#=12*151=1812N#