A block of mass m1 = 1 kg rests on a table with which it has a coefficient of friction µ = 0.77. A string attached to the block passes over a pulley to a block of mass m3 = 3 kg. The pulley is a uniform disk of mass m2 = 0.4 kg and radius 15 cm. As the mass m3 falls, the string does not slip on the pulley.
a) With what acceleration does the mass m3 fall?
b) What is the tension in the horizontal string?
c) What is the tension in the vertical string?
torque = I (alpha)
F = ma
I = .5mr^2
The Attempt at a Solution
So far I have the equations:
T1 - (mu)N = (m1)a
T2 - (m3)g = (m3)a
And I'm not sure what to do with the torque equation. I think it's
(T1)r - (T2)r = (.5mr^2)(alpha).
Is this right?
What am I doing wrong? Everytime I try something it seems to be incorrect (it's an online program that we input our answers in).