(A) An electron follows a helical path in a uniform magnetic field of magnitudes 0.3T. The pitch of the path is 6.0 μm and the electron speed is 65km/s. What is the magnetic force strength?

(B) A positive particle moves with velocity, V = (5 m/s) î+ (6 m/s) through a uniform magnetic field B = (0.03 T) î- (0.2 T)ĵ. Find the force on the positive charge due to magnetic field?