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ba726
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Homework Statement
An electric motor can accelerate a Ferris wheel of moment of inertia 19200kgm2 from rest to 9.11 rev/min in 10.7s. When the motor is turned off, friction causes the wheel to slow down from 9.11 rev/min to 7.36 rev/min in 9.55s. Determine the torque generated by the motor to bring the wheel to 9.11 rev/min. Answer in units of Nm. Also, determine the power needed to maintain the rotational speed at 9.11 rev/min. Answer in units of W.
Homework Equations
torquenet= Inertia x angular acceleration
angular velocity (final)= angular velocity (initial) + ang accel x time
Power=torque x ang velocity
The Attempt at a Solution
I already found part 1, the torque generated by the motor (2080.257403 Nm) and I'm completely stuck on part 2. I don't know if I'm doing it wrong or what. I originally used the torque from the motor times the ang velocity converted to radians/s from rev/min. I've used net torque times the same ang velocity. I forgot to convert the 9.11 ang velocity so I've used both torques with ang velocity in rev/min. What am I doing wrong?!?