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Anonymous Poster #1

Centrifugal Force Acting on Rigid Body When it is Rotating

01/19/2013 4:20 AM

when we are considering centrifugal force on the liquid element of rotating tank,the radius is should take on which surface of liquid element that is on top or bottom or in between two surfaces of the element.

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#1

Re: centrifugal force acting on rigid body when it is rotatingg

01/19/2013 4:33 AM

What did your Instructor/ Professor tell you? Did you miss that lecture and notes? Come back when you have something other than HOME WORK. You need to do you own research and find your own answers. I did!! You sound a lot like this AP, http://cr4.globalspec.com/thread/82752?frmtrk=cr4sd#newcomments

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#2

Re: centrifugal force acting on rigid body when it is rotatingg

01/19/2013 9:55 AM

Your heading says "centrifugal force acting on rigid body when it is rotating", your question says "centrifugal force on the liquid element of rotating tank". Which is it?

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#3

Re: centrifugal force acting on rigid body when it is rotatingg

01/19/2013 10:19 AM

Only one answer per customer.

We've already discussed this with you. The subject had to do with an airplane fuel tank, and it hasn't changed.

If you lost the answer, maybe you put it inside your text book.

Do you have a dog? Maybe he ate it.

Liquid Container Rotates About Horizontal Axis in Vertical Plane

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#4

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 10:54 AM

Centrifugal force is a false force. If it did exist it would cancel the real centripetal force and no movement would happen. Just like the real force of gravity on you in your chair being matched and equally opposed by the chair's real force pushing back up.

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#5
In reply to #4

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 11:04 AM

Don't encourage this joker.

Now, he'll be wanting us to explain centripetal force so he can understand it.

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#6
In reply to #5

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 11:05 AM

Aw, but I haven't abused a fool for weeks now...

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#7
In reply to #6

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 11:20 AM

Well then, go forward, my son. With my blessing.

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#9
In reply to #4

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 3:42 PM

When I was young, I used to try to slay dragons with a rock and sling. Upon release centrifugal force would cause the rock to go straight up away from the pivot point, my shoulder. I was having no luck slaying dragons or in romance.

But then, I began to believe in centripetal force, and suddenly the rock started to go forward instead. My kill rate went way up (and the rest of the story must be laid between the lines).

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#10
In reply to #9

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 5:44 PM

That's when your rock went off on a tangent?

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#11
In reply to #10

Re: centrifugal force acting on rigid body when it is rotating

01/19/2013 6:16 PM

Of course Ken is a tan gent. He lives in Georgia.

He might even enjoy southern rock.

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#12
In reply to #10

Re: centrifugal force acting on rigid body when it is rotating

01/20/2013 1:05 AM

Any day when my rock goes off (tangent or not) is a good day.

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#15
In reply to #4

Re: centrifugal force acting on rigid body when it is rotating

01/21/2013 9:31 AM

We already had a discussion on this subject a couple of years ago. May I once more present my arguments. Of course if you consider a free body the changing of its trajectory requires a force directed toward the curve center thus centripetal.

This force is equal to the vectorial product of body velocity and rotation angular speed, for a circular path it is V*V/R.

But let us look at our real life how do one exert a force directed toward the rotational center ? In general with a connecting part between the moving body and the rotation center. Due to the action = reaction this connecting element will be loaded by a force equal o the above mentioned centripetal force and have the contrary direction since the sum of forces has to be zero. This force will be CENTRIFUGAL !

Funny, out of a sudden there is a centrifugal load (force) in the connecting element. If your moving body is a rocket then the jet force will have to be centripetal since the body has no material connections with a rotating element but if you have a rock and a rope and turn the rock with the rope in your hand then the rope will pull your hand out because it has to apply the force on the rock the rope will be loaded by a centrifugal force. Any material connection between a rotating body and rotation axis will be loaded by a centrifugal force. And this is NOT in contradiction with any physical basics.

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#8

Re: Centrifugal Force Acting on Rigid Body When it is Rotating

01/19/2013 12:03 PM

Since when is liquid a rigid body?

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#13
In reply to #8

Re: Centrifugal Force Acting on Rigid Body When it is Rotating

01/20/2013 1:41 AM

If in a rotating tank it could under certain configurations be considered part of the rigid body.

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#14

Re: Centrifugal Force Acting on Rigid Body When it is Rotating

01/21/2013 4:34 AM

Rotating tanks are called centrifuges. Their purpose is to speed-up the separation of liquids and suspended solids.

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