# Center of mass help

1. Oct 31, 2007

### daniel1211

i am having some trouble understanding the concepts of center of mass for example using the equation (m1x1+m2x2)/(m1+m2) if m2>m1 what would be the center of mass i am not sure where to even begin

2. Oct 31, 2007

### D H

Staff Emeritus
You have the correct equation. You need the two masses (m1 and m2) and their position vectors (x1 and x2). Once you have those, applying the equation is very simple math.

3. Oct 31, 2007

### Feldoh

Without anymore information I think the only thing we could see is that the COM would be on the same plane as m1 and m2 and between the two masses but a little closer to m2 since it is the larger of the two.

4. Oct 31, 2007

### pmb_phy

I recommend that you follow the derivation for the expression for the center of mass at a web page I created just to explain this subject. Its at

http://www.geocities.com/physics_world/mech/center_of_mass.htm

Try it for the case of two particles.

I'll be glad to help further if needed.

Pete

5. Oct 31, 2007

### pmb_phy

daniel1211 - I want to welcome you to the Physics Forums!

My all your experiences here be good ones.

Pete