a) The earth mac field is 5*10^-5T. an electron of 3*10^4 eV cosmic ray is moving in a plane which is perpendicular to the lines of the earth mag. field. calculate the speed of the electron to determine the mag. force on this electron
b) assume the electron #a is moving in circular orbit c) at fermilab accelerator, protons of momentum 5.3*10^-16 SI are held in a circular orbit by a vertical mag. field. calculate the required magnetic field to accomplish this.