1. A +6 nC, (nanocoulomb), charge is 15 cm from an +8 nC charge.

a. What is the force between them?

b. Is the above force attractive or repulsive?

2. A 3.2 x 10^-5 charge is located on the x-axis at x=-0.8 m. A 2.5 x 10^-5 charge is located on the x-axis at x=1.3m. A 2 x 10^-5 charge is located at the origin (x=0). Find the net force on the 2 x 10^-5 charge.

3. Calculate the net charge of a neutral substance that:

a. Gains 3 x 10^12 electrons

b. Loses 7 x 10^4 electrons

c. Has a total of 6 x 10^11 protons and 9 x 10^11 electrons

4. A neutral object gains 2.5 x 10^9 electrons and is held 25 cm from a sphere with a charge of 1.2 uC. What is the force between the two objects?