Chapter 28, Problem 28.6E

Positive point charges q = +8.00 μC and q' = +3.00 μC are moving relative to an observer at point P, as shown in Fig. E28.6. The distance d is 0.120 m, ʋ = 4.50 × 10⁶ m/s, and ʋ ' = 9.00 × 10⁶m/s (a) When the two charges are at the locations shown in the figure, what are the magnitude and direction of the net magnetic field they produce at point P? (b) What are the magnitude and direction of the electric and magnetic forces that each charge exerts on the other, and what is the ratio of the magnitude of the electric force to the magnitude of the magnetic force? (c) If the direction of $\stackrel{\to }{\upsilon \text{'}}$ is reversed, so both charges are moving in the same direction, what are the magnitude and direction of the magnetic forces that the two charges exert on each other?

Figure E28.6