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jillholiver
Mar 4, 2007, 06:09 PM
I am doing extra work in my college physics course to try to get in a groove with parallel forces and center of gravity problems. I am stuck. I have navigated my online membership course, RapidMastery for Physics, and I'm still stuck. Any helpful explanations would be appreciated. The problem is this:
The uniform bar is 5.00m long and swighs 975N. A weight of 255N is attached to one end while a weight of 375N is attached 1.50m from the other end. A. Find the tension in the cable. B. Where should the cable be tied to lift the bar and its weights so that the bar hangs in a horizontal equilibrium position?
I am working in circles and need help.
Thank you.
Jill

Capuchin
Mar 5, 2007, 12:29 AM
What cable??

jillholiver
Mar 5, 2007, 05:04 AM
The cable is positioned at the 2.00m mark of the cable, labeled in the diagram (sorry!) as F4. The tension of F4 is the "cable".
Jill

Capuchin
Mar 5, 2007, 05:31 AM
I don't see a diagram, this is the problem. So I'm just going on your description, I will have a look at this in a bit.

Edit: another question, is the cable the pivot point?

Capuchin
Mar 5, 2007, 08:28 AM
Since this seems to me to be a basic moment calculation, I will give you the three equations you need:

These apply for a stationary pivoted system:

Moment about pivot = Perpendicular Force x Distance from pivot

Clockwise moment = Anticlockwise moment

Downward force = Upward force

This should be enough for you to do it yourself, but if you need help please feel free to ask :)

jillholiver
Mar 5, 2007, 02:13 PM
The cable is not the pivot point. The pp is set at the right end of the 5.0 meter bar.
Jill

jillholiver
Mar 5, 2007, 02:14 PM
Thank you, capuchin.
Jill

Capuchin
Mar 5, 2007, 02:21 PM
How are you doing with it? A picture would be useful :)

jillholiver
Mar 5, 2007, 02:26 PM
I'm on my way back to class. I'll work on it tomorrow and update you then.
Thanks so much.
Jill

Capuchin
Mar 5, 2007, 02:31 PM
Okay :)

turin
Jan 25, 2013, 05:55 AM
How can I find the center of gravity