Question
The elemental unit of charge is "e" and has the value 1.6 times 10^-19 C. How many elemental charges (how many "e") are there on each sphere? You are given charges of indeterminate value and distance. All you know is the sings (+ or -) on the (equal) charges Show the direction of the force vectors on charge 2 from the other two Then with a dark arrow indicate the direction of the net (combined) force vector on charge 2. Two insulated spheres have equal but opposite charges of 5 mu C. They are separated by a distance of 20 meters. What is the magnitude of the force on each sphere?
Explanation / Answer
Given
Charge on the spheres
Q1 = 5 x 10-6 C
Q2 = -5 x 10-6 C
k = 9 x 109 Nm2C-2
r = 20
Solution
Force F = kQ1Q1/r2
F = 9 x 109 x 5 x 10-6 x (-5 x 10-6)/202
F = -0.5625 x 10-3 N
the negative sign indicates that the force is an attractive force and its magnitude is 0.5625 x 10-3 N