# Late night physics question

Discussion in 'The Lounge' started by afroman006, Mar 3, 2006.

1. ### afroman0061/2 ton status

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I am stuck on this damn problem and cannot go on with my homework until I get it.

The background info is this is some gay spinning ride that a person leans against the wall and once it gets up to speed the floor drops away and the person stays there stuch against the wall.

What is the minimum coefficent of static friction of the ride if the person is not to slide downward if the radius of the cylinder is 3.5 meters and a constant rotation rate of 0.50 rev/sec? Give your answer with two decimal places.

The correct answer is meu (coefficent of friction) is 0.28 but for the life of me I cannot get this damn thing right. I have figured that the radial acceleration is 34.54 m/s^2 and the velocity is 11.00 m/s but that is all I can figure out.

2. ### 84k51/2 ton status

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Fgravity=Fgayspinningwheel

m= mass person
u= coefficient of friction

mg=mau

m cancels

9.81=34.54u

u=0.2837

You did the hardest part.

3. ### 84gmcjimmy1 ton status

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A little off topic, but I went on one of those rides a few years ago when the carnival came. It was scaaary. But no one fell.

4. ### kyser_soze1/2 ton status

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What's really scary is when someone pukes it hits the next 4 people

5. ### afroman0061/2 ton status

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Thanks for the help. I asked my prof this morning and he said the same thing. I knew mass was involved somewhere but it wasnt given, and for whatever reason I just didnt think about relating two equations...

Gee wizz physics is fun. Steve, this is what you have to look forward to.

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