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comment by mknod
mknod  ·  1671 days ago  ·  link  ·    ·  parent  ·  post: Hubski Physics Quiz: the monkey's wheel

After drawing 3 free body diagrams, but not actually testing, I am thinking that the normal force against the wheels will stop the machine from turning.

This is because of the actions acting against the wheels, vs the wheels acting against the disk.

Good puzzle.

EDIT: Is this a frictionless table?

wasoxygen  ·  1671 days ago  ·  link  ·  

No, the surface is not frictionless.

Is your prediction that the car will not move at all?

mknod  ·  1670 days ago  ·  link  ·  

Sorry I have another question. Does the wheel interlock with the other wheels or are they all just circular?

If they interlock then I'm going to say that it doesn't move due to the configuration of the gears.

If they do not interlock, then I am going to say that the wheels will move in the opposite direction of the big wheel.

wasoxygen  ·  1670 days ago  ·  link  ·  

The wheels do not lock together; they are smooth and round with no gears.

We want to figure out what the entire car will do when the top of the big wheel is pushed to the right. Will it roll? Right or left?

mknod  ·  1669 days ago  ·  link  ·  

Moving the ruler to the right will make the big wheel move counter clockwise the smaller wheels move clockwise.

mknod  ·  1671 days ago  ·  link  ·  

Well initially, that was what I was thinking. But then I started thinking about some of the odd (unintuitive) gears I've seen:

I will have to think about this more after work.