A cyclotron is designed so that the charged particles always circulate in a dee of…
PHYSICS · Subjective · AP · Physics 2: Algebra-based · Magnetism and Electromagnetism · Magnetism and Electromagnetism
Problem
A cyclotron is designed so that the charged particles always circulate in a dee of fixed radius 0.50m. Protons of charge e and mass mp are accelerated from an initial kinetic energy of 1.0MeV to 4.0MeV while remaining inside the same circular orbit.
(i) Show that, for a constant orbital radius, the magnetic field required is proportional to the square root of the kinetic energy of the proton.
(ii) The magnetic field in the cyclotron is initially 1.5T when the proton energy is 1.0MeV. Calculate the magnetic field needed when the proton energy reaches 4.0MeV.
(iii) Determine the speed of the proton at 4.0MeV and comment, with reason, on whether any relativistic correction is necessary at this energy for routine laboratory calculations.