Amagnetic field of 0.1 t 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. 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?
0 j

10-22 j

10-5 j

102 j

1020 j

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c