# Center of Mass - Ax

1. Feb 11, 2009

### tascja

1. The problem statement, all variables and given/known data
alley club-ax consists of a symmetrical 8 kg stone attached to the end of a uniform 2.5 kg stick that is 98 cm long. How far is the center of mass from the angle end of the club-ax?

2. Relevant equations
Xcm = (sum) x*m / m

3. The attempt at a solution

I dont know how to approach this.. do i put the ax on a coordinate plane?
and it says that it is it is symmetrical and of uniform weight, does that give extra information that i should be using?

2. Feb 11, 2009

### LowlyPion

Not sure which is the angle end, but say it is the handle. You can reverse it if not.

The handle is .98m and uniform density. You could take the integral of that to find the center of mass of just the handle, but I'm sure you know already it's in the middle for the handle part. To complete the sum of the moments for the whole shillelagh, then add the moment of the stone at the end.

So with ms the mass of the stone, mh the mass of the handle, and xh the center of mass of the handle,

Xcm = (xh*mh + L*ms)/(mh + ms)