A light bulb uses 20.0 watts of power when connected to a 120 volt wall socket. How much electric current does the bulb draw from the wall socket? Round to 2
decimal places in your answer and include the unit for current in your answer. (AKS
8b)

If two metal balls each have a charge of -10^-6 c and the repulsive force between them is 1 n, how far apart are they? (coulomb's constant is k = 9.0x 10^9 n-m^2/c^2? 9.5 m 9.0 mm 9.5 cm 0.9 m .

Find the magnetic field a distance r from the center of a long wire that has radius a and carries a uniform current per unit area j in the positive z direction.

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?