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elizabethg
Nov19-04, 12:37 AM
I need help on a problem, I tried using many equations, what do I do?...

A m1=13.5kg object and a m2=12.5kg object are suspended, joined by a cord that passes over a pulley with a radius of 10 cm and a mass of 3 kg. The cord has a negligible mass and does not slip on the pulley. The pulley rotates on its axis without friction. The objects start from rest 3 m apart. Treating the pulley as a uniform disk, determine the speeds of the two objects as they pass each other.

I used the equation to find acceleration...

a=((m1-m2)g)/(m1+m2+.5mR^2) The .5mR^2 is the moment of Inertia

After I found the acceleration I found the velocity...

v=(2a(x/2))^(1/2)

Please Help

kakarukeys
Nov19-04, 06:56 AM
My first thought:
Use conservation of energy to work for you
Here the kinetic energy of both masses + potential energy of both masses + rotational energy of the pulley is conserved.