Singly ionised helium nuclei are accelerated in a cyclotron whose dees are separated…
PHYSICS · Subjective · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism
Problem
Singly ionised helium nuclei (q=1.6×10−19C,m=6.64×10−27kg) are accelerated in a cyclotron whose dees are separated by a small gap across which a peak potential difference of 50kV is applied each half cycle. The magnetic field inside the dees is uniform and has a magnitude of 1.2T.
(i) Calculate the operating frequency required for the accelerating voltage.
(ii) Show that each time a helium nucleus crosses the gap it gains the same amount of kinetic energy and determine this energy gain per revolution.
(iii) How many complete revolutions must a helium nucleus make inside the machine in order to reach a kinetic energy of 4.0MeV?