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schoolgirl
We're currently learning about centripetal acceleration and force in class, and this homework problem just stumped me. I don't know which formula to use for this one. Should I use Fa=mvsquared/r since they tell you the radius, which is 0.6m? I'm confused once again! Please help!

problem:
A popular trick of many physics teachers is to swing a pail of water around in a vertical circl fast enough so that the water doesn't spill out when the pail is upside down. If Mr. Lowell's arm is 0.6m long, what is the minimum speed with which he can swing the pail so that the water doesn't spill out at the top of the path?
Moseley
Hi - when I saw your thread title I thought of mrw^2 - where w is the angular velocity in radians. This is the answer but I'll let you research it from a good source:

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

Click on mechanics then circular motion, then angular velocity and you will see how w is derived.
As usual if there are any steps in the working that you are not happy with then just let us know.
MV
User posted image

Not wanting to give the answer out right, but it is approx. 2.4 m/s

here is a very good link for all things "physics"...

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
MV
Darn it, Moseley!

You beat me to it!!! laugh.gif
Moseley
Sorry about that - it took me 10 mins or so to post so it was close between us.
Anyway, as they say - great minds...
Drude
when a guy posts, nobody is there to answer him maybe except me and mosley and when a "girl" posts, people are just dying to race to save her...lovely.

Well, Mosley and MV have spoken. Not much to add. Good luck.
Upisoft
QUOTE (Drude+Feb 10 2006, 07:37 PM)
when a guy posts, nobody is there to answer him maybe except me and mosley and when a "girl" posts, people are just dying to race to save her...lovely.

Perhaps the "schoolgirl" could be just clever "schoolboy". biggrin.gif
Drude
QUOTE
Perhaps the "schoolgirl" could be just clever "schoolboy".


very scary laugh.gif . No this is not at her. She has every right to ask a question and I would answer her with the best of my knowledge but just mentioning the undeniable: Sex sells, and gets ur homework done lol biggrin.gif
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