# Block on Block Dynamic Question

1. Oct 17, 2008

### wby

I was wondering if anyone knows the answer to this question:

1. The problem statement, all variables and given/known data

consider 2 blocks of masses m1 and m2. the block of mass m1 is resting on top of the block m2 which in turn is resting upon a horizontal surface. The coefficient of static friction between the 2 blocks is u1 and the coefficient of the kinetic friction between the lower block and the horizontal surface is u2. A force, F, is being applied to the bottom block at angle0 to the horizontal, and the 2 blocks are moving together in the horizontal direction.

2. Relevant equations

a. Draw a free body diagram (Best if drawn, but I think I can still manage without it)

b. write equations representing newton's 2nd law for each of the above diagrams. For each diagram add equation(s) representing the relationship between frictional and normal forces

c. wut is the acceleration of the bottom block?

d. What is the maximum force, F max, that can be appled before the top block slips?

3. The attempt at a solution

No idea...

Thanks a lot for the help!
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Oct 18, 2008

### tiny-tim

Welcome to PF!

Hi wby! Welcome to PF!

Show us what you've tried, and where you're stuck, and then we'll know how to help.