Hey guys, I'm working on a homework problem about nuclear fusion in stars and am..stuck on the first step: calculating the temperature needed for protons to come within 2 fm of one another and overcome Coulomb repulsion. 1. The problem statement, all variables and given/known data Given that the protons have an average kinetic energy (3/2)kbT, and in the Boltzmann distribution there will be some protons of 4 times that energy, show that a temperature of about a billion degrees Kelvin is needed in order for the protons to overcome the Coulomb repulsion and approach each other within 2 fm. 2. Relevant equations avg KE = (3/2)kbT Coulomb Barrier: U = ke2/r 3. The attempt at a solution I calculated U to be 1.4 * 106eV. I then plugged this in as an inequality, where the avg KE > U and solved for T, which I found to be 1.08*1010K. I'm certain I missed something, or a lot of something, but I don't know what that is. I'm meant to use the finite-structure constant α = 1/137, right?