The 10 lb block A
and the 20 lb block B are initially at rest. If a force of P = 10 lb is
applied to B as shown, determine the accleration of each block. The coefficient
of kinetic friction between any two surfaces is
mk
= 0.2 and the coefficient of static friction is
ms = 0.3.Note that
A slips on B.
1) 6.44 ft/s2 and
3.22 ft/s2
2) 5.5 ft/s2 and 4.23 ft/s2
3) 1.38 ft/s2 and 2.38 ft/s2
4) 6.25 ft/s2 and 3.28 ft/s2
Since A slips on B
as B slips:
For block A: S Fx = max
( from the free body of A)
2 = (10/32.2)aA and aA = 6.44
ft/s2
For block B: S
Fx = max (from the free body of B)
10 - 6 -2 = (20/32.2)aB and aB = 3.22 ft/s2
So the accleration
of A, aA = 6.44 ft/s2
and the accleration of B, aA = 3.22 ft/s2