An object with a mass of #7 kg# is on a surface with a kinetic friction coefficient of # 8 #. How much force is necessary to accelerate the object horizontally at # 31 m/s^2#?

1 Answer
Dec 30, 2015

I found #765.8N# (but check my maths!). Ciao.

Explanation:

Have a look:
enter image source here
So we get that:
#N=W=mg=7*9.8=68.6N#
From the first equation (alomg #x#) we get:
#F-mu_kN=ma#
#F=(8*68.6)+(7*31)=765.8N#