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sealedhuman77
Mar25-08, 01:15 PM
1. The problem statement, all variables and given/known data

Massive spinning flywheels (disks) can be used for storing energy. Consider a flywheel with a diameter of 1.10 m and a mass of 510 kg. A constant force of magnitude F is applied tangentially to the rim of the flywheel to accelerate it from rest to 4.00 x 103 rev/min during 2.85 min.

(b) What magnitude of torque is necessary to cause this angular acceleration?

2. Relevant equations

I = mR^{2}
\tau = I\alpha

3. The attempt at a solution

I = mR^{2}
I = (510kg)\ast(.55m)^{2}
I = 154.275 kgm^{2}

\tau = I\alpha
\tau = (154.275kgm^{2})\ast(2.449rad/s^{2}
\tau = 377.819 Nm

The answer was incorrect. Also the angular acceleration was derived from part a and is the correct number. Thanks for the help.

sealedhuman77
Mar25-08, 01:17 PM
the Tau and Alpha symbols are not suppose to be superscripts. i screwed up the tex