Two small plastic balls hang from threads (1m long) of negligible mass. Each ball has a mass of 0.09 g and equal charges. The balls are repelled with each other .they are 18cm apart and the threads attached to the balls make an angle of 25 degree with the vertical. Decide:
1. The tension in each of the threads.
2. The magnitude of the charge q on the balls.
3. The magnitude of the electric force acting on each ball.