# Help With Pulleys

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1. Oct 14, 2016

### stephhm

• Member advised to use the homework template for posts in the homework sections of PF.
A block of mass m1 is attached to a block of mass m2 by a massless rope (see diagram); the pulleys and surfaces are frictionless. When the blocks are let go, they move. Answer the following three questions using the choices given below.

i) Select the correct expression for the relationship between the accelerations of blocks 1 and 2.
ii) Select the correct expression that describes how the magnitude of the acceleration of block 1, a1, depends on the tension in the rope, T.
iii) Select the correct expression that describes how the magnitude of the acceleration of block 2, a2, depends on the tension in the rope, T.

The expressions and diagram are attached.

For i) I said O because acceleration of 2 must be going down?
For ii) I have no idea
For iii) I said A because the tension must be divided by mass 2 since it's the one going down?

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2. Oct 14, 2016

### haruspex

In the given coordinates, is 1's acceleration positive or negative? Is 2's acceleration positive or negative?
If 1 moves left a distance s, how does 2 move?
What forces act on 1?
What forces act on 2?