Blocks on a tabletop attached to a mass suspended by a pulley

1. Feb 3, 2009

Wobble

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

2. Relevant equations

We have yet to go over this material, which kinda pisses me off, but I'm guessing that:

f=ma, w=ma, g = 9.8m/s/s

are important

3. The attempt at a solution

If somebody could point me in the right direction that would be very helpful. I attempted at drawing a diagram of the forces on each object, but I'm not sure where to even start.

2. Feb 3, 2009

needlottahelp

You want to find the mass of block C so that it moves block A but not too large that it overcomes the static friction between block A and block B I believe. So find the static friction and divide it by g to find the mass of Block C

static friction = (coefficient of static friction) (reaction/normal force)

3. Feb 3, 2009

Wobble

So will the normal force be the mass of the two blocks times gravity?

4. Feb 3, 2009

needlottahelp

the normal force should be equal to the weight of Block B

5. Feb 3, 2009

Wobble

Thank you so much

I got 3.75 kg