1. What is the magnitude of the force on a change of +2 x 10-7C that is 0.3m from a charge of -5 x 10-7C?
Answer: 10-2N attractive force.
2. Two electrons repel each other with a force of 10-8N. How far apart are they?
Answer: 1.5 x 10-10m
3. A test charge of +2 x 10-7C is located 5cm to the right of a charge of +1 x 10-6C and 10cm to the left of a charge of -1 x 10-6C. The three charges lie on a straight line. Find the force on the test charge.
Answer: 0.9 to the right
4. Three +100-statC charges are arranged in a straight line, the second charge (B) is 20cm to the right of the first (A) and the third (C) is 50cm to the right of A. What is the force exerted by charges A and B on C?
Answer: 15.1 dyu