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MagLok
Feb26-08, 08:47 PM
1. The problem statement, all variables and given/known data
http://img258.imageshack.us/img258/7172/testiiifo2.jpg Here is an image of the problem (taken from a practice test.)


2. Relevant equations
F=ma


3. The attempt at a solution
I drew the free body diagrams for each, but I have no idea what the equation would be. I came up with equations for each mass, and solved for a in one, plugged into the other and got this.

Tension Force (string, m2) - Grav Force (earth, m2)=M2*((-tension force string, M1)/m1)

This doesn't appear to me to be a position equation.. please help.

MagLok
Feb26-08, 09:30 PM
If this is not descriptive enough, please let me know and I'll run to my friend's house and scan my work.

Runelord
Feb26-08, 09:55 PM
Well, if you draw the free body diagram for figure 2, you simply have for each part, the one sitting on the table is:

Tension = m1 * a

The one hanging is:

mg - Tension = m2 * a

Plug in for the tension:

mg - m1 a = m2 * a
mg = (m1+m2) a
a = m/(m1+m2) * g

So you would need to plot m/(m1+m2) on the x axis. Hope this helps.

MagLok
Feb26-08, 10:19 PM
Yes, thank you much Runelord :-D