Q. A point charge of -7pC is concentric with two spherical conducting thick shells, as show in the figure below. The smaller spherical conducting shell has a net charge of -22 pC and the larger spherical conducting shell has a net charge of 12pC. What is the charge on the inner surface of the small spherical conducting shell, 2.8cm from the -7pC point charge? Under static conditions, the charge on a conductor resides on the surface of the conductor.
Q. A certain car battery with a 12.0 V emf has an initial charge of 115 A·h. Assuming that the potential across the terminals stays constant until the battery is completely discharged, for how many hours can it deliver energy at the rate of 110 W?