# earth rotation/in ground hoist

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I have an in ground hydraulic automobile hoist and do not have a non-rotator. When lifting the vehicle up or letting it down it will always rotate. Does this have anything with the earths rotation?

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Yeah, that's it. Like if you fired a smooth-bored muzzle loader straight up in the air, the ball would rotate for the same reason. Also why footballs spin - they are given an upward component when thrown.

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It may have more to do with the earth's gravity. The heaviest end of the car is probably headed for the lowest point in the circle due to the hoist not being perfectly vertical.

Fred

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Coriolis effect. It would rotate the opposite direction in the Southern hemisphere.

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Where do you live?

Nick

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Nah.... It's due to the fact that the piston ring seals are skive-jointed, rather than continuous. They act as "hydraulic screws" when moving in a smooth bore. Virtually all hydraulic cylinders with skived rings will rotate one way on extend, and the other way on retract. There doesn't need to be a large mass at the end of the effector to cause it.

The Coriolus Effect is so weak that the friction between seals and cylinder wall would prevent it if they were continuous rings, and overcome it when they are skived.

LLoyd

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tis the evil spirits tugging on the bumpers

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"mark" wrote: (clip) When lifting the vehicle up or letting it down it will always rotate. Does this have anything with the earths rotation? ^^^^^^^^^^^^^^ Obvious question: Does it rotate in the opposite directions coming down vs going up?

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Is there beer involved? Is the car still and the Earth spinning?

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Does it spin the opposite direction if you hoist a right-hand drive car?

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beer involved? Is the car still and the Earth spinning?

Are we sure we cant blame it on global warming and then GWB ?

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This would have to be the most entertaining answer so far.

My oldest brother taught me long ago that when you're lying in bed, and the spinning gets violent, if you kick the floor hard enough in the opposite direction, you can stop the rotation.

As it turns out, he lied to me.

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Actually, you can usually stop the rotation as long as you keep your foot on the floor...

Don't try this if you have the upper bunk (leftover knowledge from my Navy days....).

Jerry

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mark are you at the north pole or the south?

....it doesnt matter. NO. the earth's angular rotation is 15 degrees an hour. I'll bet it is a lot faster than that.

Stealth Pilot

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"Jon" wrote: (clip) My oldest brother taught me long ago that when you're lying in bed, and the

^^^^^^^^^^^^^^^^^^ He wasn't lying. You didn't kick hard enough.

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