## Wheel and Axle

ericlepanda
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State: IL

### Wheel and Axle

Will a wheel and axle rolling down a ramp on its axle, and then hitting a lever, count as a wheel and axle? Gravity is the input force on the axle, and the wheel has an output force on the lever.
quack quack

chalker
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### Re: Wheel and Axle

ericlepanda wrote:Will a wheel and axle rolling down a ramp on its axle, and then hitting a lever, count as a wheel and axle? Gravity is the input force on the axle, and the wheel has an output force on the lever.

Here's a good rule of thumb in answering questions like this: would the device still work if the wheel was able to spin freely on the axle? If so, you aren't using the wheel and axle as a simple machine to gain mechanical advantage and it's not within the rules.

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Uncle Fester
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### Re: Wheel and Axle

Agreed. You're not using a wheel and axle; you happen to be using a friction-reducing device.

Dunno if you were planning on 'pointing' the ramp, but inclined plane WORK needs to go uphill.
Uncle Fester, Maker & Fiction Science Writer

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Nair
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### Re: Wheel and Axle

Does this mean a wheel and axle need to work in place and not move along even a horizontal surface?

One of our wheel and axle work like this: A golf ball rolls down and hits the axle of the wheel. This pushes the wheel and axle forward on a horizontal surface.
Would it be considered a wheel and axle?

chalker
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Joined: January 9th, 2009, 7:30 pm
State: OH

### Re: Wheel and Axle

Nair wrote:Does this mean a wheel and axle need to work in place and not move along even a horizontal surface?

One of our wheel and axle work like this: A golf ball rolls down and hits the axle of the wheel. This pushes the wheel and axle forward on a horizontal surface.
Would it be considered a wheel and axle?

I'll point back to my general advice above "Here's a good rule of thumb in answering questions like this: would the device still work if the wheel was able to spin freely on the axle? If so, you aren't using the wheel and axle as a simple machine to gain mechanical advantage and it's not within the rules." and also recommend you read the Wikipedia page on Wheel and Axle: https://en.wikipedia.org/wiki/Wheel_and_axle

Student Alumni
National Event Supervisor
National Physical Sciences Rules Committee Chair