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Homework Statement
A vertical grinding wheel is a uniform disk of mass 62 kg and radius 45 cm. It has a handle of radius 69 cm of negligible mass. A 25-kg load is attached to the handle when it is in the horizontal position.
(a) Neglecting friction, find the initial angular acceleration of the wheel in rad/s^2.
(b) Find the maximum angular velocity of the wheel in rad/s.
Homework Equations
I = 1/2MR^2 + mr^2
t = mgr for torque
a = t/I for angular acceleration
mgr = 1/2Iw^2
The Attempt at a Solution
a) Neglecting friction, find the initial angular acceleration of the wheel.
9.31 rad/s^2
I found I which is 18.18 kg m^2 using the above equation.
I then gound T(t) which is 169.23 Nm
a = t/I = 9.31 rad/s^2
(b) Find the maximum angular velocity of the wheel.
I used mgr = 0.5Iw^2 and got w = 3.32 rad/s
***What am I doing wrong?? I know both are wrong answers. I think I am doing something wrong for part a. Please help!
Thanks