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Sumbhajee
Oct8-09, 11:53 AM
1. The problem statement, all variables and given/known data
How many revolutions per minute would a 15.1 m diameter Ferris wheel need to make for the passengers to feel "weightless" at the topmost point of the trip?


2. Relevant equations



3. The attempt at a solution
I assume this problem has something to do with finding acceleration and converting from there. I have been having a lot of trouble with this problem.

rl.bhat
Oct8-09, 11:59 AM
What are the things you know about vertical circular motion?

Sumbhajee
Oct8-09, 12:07 PM
I know that Centripetal acceleration = (velocity)^2/radius

gamer_x_
Oct8-09, 12:12 PM
If you're weightless at the top, what does that mean? Draw your free body diagram, then figure out which forces are acting where.

rl.bhat
Oct8-09, 12:15 PM
I know that Centripetal acceleration = (velocity)^2/radius

Can write this in terms of angular velocity?
What happens at the top of the wheel?

Sumbhajee
Oct8-09, 12:16 PM
If you are weightless at the top you should have mass * gravity acting down and a centripetal force equal to gravity acting up. But how does this information help to discover revolutions per minute?

Sumbhajee
Oct8-09, 12:19 PM
To set up the equation would I use the following:

9.80=V^2/7.55 and solve for velocity? But how do you convert velocity to revolutions per minute?

Sumbhajee
Oct8-09, 03:30 PM
I found the answer! Thank you for all the help.