Q11: The electron beam emerging from a certain high- energy electron accelerator has a circular cross section of radiusmm.
(a) The beam current is mA. Find the current density in the beam assuming it is uniform throughout.
(b) The speed of the electrons is so close to the speed of light that their speed can be taken as Mm/s with negligible error. Find the electron density in the beam.
(c) Over what time inter- val does Avogadro’s number of electrons emerge from the accelerator?