Question

1. A charge of −0.0004 C is a distance of 3 meters from a charge of 0.0003 C. What is the magnitude of the force between them?

Answer 1

q1= charge 1 = -0.0004C

q2= charge 2 = 0.0003c

r = distance = 3 m

F = k (q1*q2) / r^2

Where:

F= force

k= constant = 9 x 10^9 kgm^3/s^2m^2

Replacing:

F = 9x10^9 ( -0.0004 * 0.0003 ) / 3^2

F= 120 N