Answer to Question #89705 in Electricity and Magnetism for Khadeeja

Question

Two charged particles M and N enter a region of uniform magnetic field with velocity is perpendicular to the field. The parts of the particles as shown in the figure(N has a higher radius than M). The possible reason is,
(1) the charge M is greater than that of N
(2) the momentum of M is greater than that of N
(3) the charge to mass ratio of M is greater than that of N
(4) the speed of M is greater than that of N
(5) none of the above

Answer 1

The magnetic force supplies the centripetal force

$$Bqv=\frac {mv^2}{r} (1)$$

Using (1) we get

$$r=\frac {mv} {Bq}$$

Answer:

(1) the charge M is greater than that of N