## Questions 31-32
A magnetic field of 0.1T forces a proton beam of 1.5 mA to move in a circle of radius 0.1 m . The plane of the circle is perpendicular to the magnetic field.
32. Of the following, which is the best estimate of the speed of a proton in the beam as it moves in the circle?
(A) 10−2m/s
(B) 103m/s
(C) 106m/s
(D) 108m/s
(A) 10−2m/s
(B) 103m/s
(C) 106m/s
(D) 108m/s