## 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.
31. Of the following, which is the best estimate of the work done by the magnetic field on the protons during one complete orbit of the circle?
(A) 0 J
(B) 10−22J
(C) 10−5J
(D) 102J
(A) 0 J
(B) 10−22J
(C) 10−5J
(D) 102J