- #1

snoopies622

- 846

- 28

- TL;DR Summary
- I'm having a math problem with Gauss's law for gravity for a point mass M. Or is my interpretation of the law wrong?

i have little experience with the differential form of Gauss's Law, and I've tried three times now to arrive at it for a point mass M (spherically symmetric classical gravitational field) but instead of getting an answer proportional to the mass density I keep getting zero. Is the divergence supposed to be zero? Intuitively I would say no since all the field lines are pointing away from the origin, but then maybe the fact that they get smaller as r increases makes a difference. Scanned and uploaded my work since LaTeX can be a bit tedious.