Weightlessness on a Ferris Wheel

[Sumbhajee]

Homework Statement

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?

Homework Equations

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]

What are the things you know about vertical circular motion?

 

[Sumbhajee]

I know that Centripetal acceleration = (velocity)^2/radius

 

[gamer_x_]

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]

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]

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]

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]

I found the answer! Thank you for all the help.