Compute each part of given problem:
Problem: In a certain particle accelerator, a proton beam with a diameter of 2mm constitutes a current of 1mA. Each proton has kinetic energy of 20MeV. The beam strikes a metal target and is absorbed by it.
Part A: What is the proton density within the beam? This is not the density of a proton.
Part B: How many protons strike the target in one minute?
Part C: If the target is initially uncharged, describe the charge of the target as a function of time.
I need help to find how many protons strike the target in one minute.