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Homework Statement
motor is mounted on top of lift.
a)if p moves by y, what is the displacement of Pt A? Prove that V_{p}=3V_{a}.
b)If motor unwidns cable at const rate 2m/s, what is vel of cable wrt lift.
Prove vel of lift is 0.5m/s
Homework Equations
The Attempt at a Solution
I can do part a. I have prob with part b. If motor releases cable at 2m/s, can i take it that pt p moves 2m/s. so V_{a} is 2/3=0.667. Since pt a is connected to the lift, the vel of cable wrt lift is 2+0.667=2.667.
But velocity of lift is 0.5 so the vel of cable wrt to lift is 2.5. This is getting confusing.
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