A charged particle (m = 5.0 g, q = -70 $\mu$C) moves horizontally at a constant speed of 30 km/s in a region where the free fall gravitational acceleration is 9.8 m/s2 downward, the electric field is 700 N/C upward, and the magnetic field is perpendicular to the velocity of the particle.What is the magnitude of the magnetic field in this region?

Question

Quizplus · Accepted Answer

The magnetic force must balance the gravitational and electric forces for the particle to move at a constant speed. Using the equation $ qvB = mg + qE $, solve for $ B $ to find the magnitude of the magnetic field.

A Charged Particle (M = 5 μ\muμ C) Moves Horizontally at a Constant Speed of 30 Km/s

A Charged Particle (M = 5 $\mu$ C) Moves Horizontally at a Constant Speed of 30 Km/s