Homework Statement
Consider an ideal system of 5 non-interacting spin 1/2 particles in the absence of an external magnetic field. What is the probability that n of the five spins have spin up for each of the cases n = 0, 1, 2, 3, 4, 5?
Homework Equations
I'm guessing \frac{N!}{n!(N-n)!}...
Homework Statement
Homework Equations
Just to clarify the question, the value given for R2 is the overall radius of Earth, it isn't R1-R2. (At least, that's my interpretation given that the R2 value is approx. the Earth's radius)
The Attempt at a Solution
Don't really know how...