# Center of Mass problem

1. Oct 25, 2007

### Bob Loblaw

[Solved]Center of Mass problem

1. The problem statement, all variables and given/known data

Jane is sitting on a chair with her lower leg at a 30.0° angle with respect to the vertical, as shown. You need to develop a computer model of her leg to assist in some medical research. If you assume that her leg can be modeled as two uniform cylinders, one with mass M1 = 18 kg and length L1 = 35 cm and one with mass M2 = 10 kg and length L2 = 36 cm, where is the center of mass of her leg?

http://www.webassign.net/grr/p7-32.gif

2. Relevant equations

M1X1+M2X2/M1+M2

3. The attempt at a solution

I attempted to break up the problem into compoents and found a cordinate system of
m1 (0,0)(0,35) and M2 as (35, 0), (53, -31.18)

I am not sure how to procede from here.

EXCITING UPDATE:

Y has been solved! I took the midpoint of the y2 cordinate which is -15.9 and multiplied that by the 10kg mass and divided by both masses. I thought this might work since the Y1 is equal to zero.

FOLLOW UP! X has now been solved! I did the same process in finding the midpoint of both X components.

The problem is now solved.

Last edited: Oct 26, 2007