1. A block of mass m=1.20 kg is stacked on top of a block of mass M=3.20 kg and the two move together on a horizontal surface with a constant acceleration of magnitude a=4.04 m/s^2 pointing to the right under the influence of an external horizontal force of manitude F0=40.3N which is applied to mass M. The coefficient between mass m and mass M is (mu)=0.780. The coefficient of kinetic friction between block m and block M is not given. The coefficient of kinetic friction between block M and the horizontal surface is also not given.
a. What is the magnitude of the force of friction exerted by block M on m?
b. What is the magnitude of the force of friction exerted by the horizontal surface on block M?
Please show your work :)
2007-10-28 10:54:38 · 1 answers · asked by carbonatedcolor 2 in Science & Mathematics ➔ Physics
a) Let's first see if m is slipping
F=1.2*4.04
F=4.848 N
Max friction before slipping is
1.2*9.81*0.780
=9.18 , nope not slipping, so the frictional force between m and M is 4.848 N
so
40.3-f=5.4*4.04
f=18.48 N
Note, I always used net force equals acceleration
F=m*a
j
2007-10-29 05:58:00 · answer #1 · answered by odu83 7 · 0⤊ 0⤋