Proton 1 , traveling in the negative \(x\) direction at speed \(v_{1}\), is directly below proton 2 , which is traveling at speed \(v_{2}\) at an angle of \(45^{\circ}\) above the positive \(x\) axis. If the protons are separated by a distance \(r\), calculate the magnitude of the magnetic force each proton exerts on the other.