1. Calculate the electrostatic repulsive force between two similarly charged objects located at 10 cm from each other. The charge on one of the objects is 10 C, and charge on the other object is 20 C. The electrostatic constant is 9 x 10⁹ N-m²/C².
2. How long does it take to charge the same battery using a fast charger with 400V that operate at 100 A.
3. The lighting and sound of thunder are generated when two clouds of opposing charge collide. In a cloudy day, you heard a sound of a thunder 10 seconds after you saw the lighting. What is the distance of the clouds from your position?