# Homework Help: Physics Hwk Problem: Centripetal Acceleration

1. Oct 24, 2004

### shawonna23

A ceiling fan has two different angular speed settings: w1 = 485 rev/min and w2 = 120 rev/min. What is the ratio (a1/a2) of the centripetal accelerations of a given point on a fan blade?

How would I go about solving this problem?

2. Oct 24, 2004

### Staff: Mentor

What's the formula for centripetal acceleration? Hint: Find the formula for centripetal acceleration in terms of angular speed ($\omega$).

3. Oct 24, 2004

### shawonna23

Physics hwk problem: Centripetal Acceleration

I used the equation: w^2=a/r. I found the angular speed, but i don't know what the radius is.

4. Oct 24, 2004

### Tide

The radius will not change between the two speed settings.