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cantdisclosename
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Homework Statement
A pulley of radius, R and moment of inertia, I=2MR^2 is mounted on an axle with negligible friction. Block A, with a mass M, and Block B, with a mass of 3M, are attached to a light string that passes over the pulley. Assuming that the string doesn't slip on the pulley, Answer the following questions in terms of M, R, and fundamental constants.
a. What is the acceleration of the two blocks?
b. What is the tension force in the left section of the string? (M is on the left hanging)
c. What is the tension force in the right section of the string? (3M is on the right)
Homework Equations
Fnet=ma
τ=Iα
The Attempt at a Solution
a. Fnet=ma
3Mg-Mg=4Ma
a=g/2
Answer: g/3
For b and c. even if I plug in the right acceleration I get the wrong answer for b but right answer for c
b. Fnet=ma
Mg-T=Ma
Mg-T=Mg/3
-T=Mg/3-3Mg/3
-T=-2/3Mg
T=2/3Mg
Answer= 4/3Mg
c. Fnet=ma
3Mg-T=ma
3Mg-T=3M(g/3)
3Mg-T=Mg
T=2mg
Answer: 2mg