# Homework Help: This should be my last one

1. Sep 13, 2006

### physics newb

OK, this should be my last question. Again, I need an answer soon, but I'm also here to learn.

Two Blocks are in contact on a frictionless table, one larger than the other. A horizontal force is applied to the larger block, pushing against the smaller block. (a) If m_A = 2.3 kg (the larger block), m_B = 1.2 kg (the smaller block), and F = 3.2 N, find the magnitude of the force between the two blocks. (b) Show that if a force of the same magnitude F is applied to the smaller block but in the opposite direction, the magnitude of the force between the blocks is 2.1 N, which is not the same value calculated in (a). (c) Explain the difference. I'm not quite sure what to do with the information given, so again, any help would be great!

2. Sep 13, 2006

### Astronuc

Staff Emeritus
One has enough information.

Since the blocks are in contact, the applied for F acts on the mass of both (both must be accelerating), BUT, the force acting on (transmitted to) the larger block by the smaller block is less than the force that the larger block would apply to the smaller block - because . . . (what does mass do?)

Think F = ma.