Question

Ok ! i need help with finding some neat way to calculate the center of mass of half a sphere =]
Thanks !!!

Answer 1

Neat way?
Use the normal one.
Assume a disk at an x distance above the centre of width dx.
Consider this your element.
Can you integrate it after this?

Answer 2

well, the x coordinate is on the 0 point because of the symetry i need the y part of the center of mass coordinate .. how do i express dm in terms of y ?

Answer 3

Well. At a distance x Assume a disk of width dx
Use mass per unit volume.
Integrate from 0 to R.