# Homework Help: Power - Ferris Wheel with friction

1. Apr 12, 2010

### MissPenguins

1. The problem statement, all variables and given/known data
A motor keep a Ferris wheel (with moment of inertia 8.95X10^7 kg X m^2)rotating at 6.3 rev/hr. When the motor is turned off, the wheel slow down (because of friction) to 3.5 rev/hr in 25 s. What was the power of the motor that kept the wheel rotating at 6.3 rev/hr despite friction? Answer in units of W.

2. Relevant equations
P = $$\Delta$$W/$$\Delta$$t

3. The attempt at a solution
Well, if I interpret it correctly, I guess I have to convert 3.5 rev/hr to rad/s. Correct? And find W by FD? Sorry, I am too sure what to do. Thanks for your help.

2. Apr 12, 2010

### MissPenguins

SORRY, someone else posted it already

3. Apr 12, 2010

### Bearbull24.5

You wouldnt by chance be in Professor Woods' class?

4. Apr 23, 2010

### MissPenguins

I am in his class. I can tell you are since you have "Bull" in your username. ;)