# Pulley Question

1. Jan 16, 2017

### RoyalFlush100

1. The problem statement, all variables and given/known data
In the picture below.

2. Relevant equations
Velocity on a pulley = (velocity on left rope + velocity right rope)/2
Pulley A and C have 0 velocity.

3. The attempt at a solution
By inspection the right sided rope on pulley A is 120 mm/s going up.
After that is when I get confused. Pulley B and D are in motion, so I don't see what else to do from here.

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Last edited: Jan 16, 2017
2. Jan 16, 2017

### haruspex

Looks like down to me.
So apply that to each pulley in turn, working from the left.
What does it tell you about the velocity of the second rope segment (the one on the right of pulley A)?

3. Jan 16, 2017

### RoyalFlush100

Yeah, I meant the rope to the right.

But still, we don't know vB, meaning we'd have:
vB = (150+vBR)/2
Where vBR is the velocity on the right of pulley B.
By inspection vCL = -vBR

But from here, I'm not sure how to proceed since vB is not 0

4. Jan 16, 2017

### haruspex

Ok.
I feel your notation is going to get a bit confusing since you will have two names for the same rope.
I'll just label them and their velocities a to e across the top, and the segment left of the lowest pulley is f.