parallel-plate capacitor in air has a plate separation of 1.56 cm and a plate area of 25.0 cm2. The plates are charged to a potential difference of 225 V and disconnected from the source. The capacitor is then immersed in distilled water. Assume the liquid is an insulator. (a) Determine the charge on the plates before and after immersion. (b) Determine the capacitance and potential difference after immersion.(c) Determine the change in energy of the capacitor.

An initially uncharged air-filled capacitor is connected to a 3.29 V charging source. As a result, the capacitor acquires 9.89 x 10- C of charge. Then, while the capacitor remains connected to the charging source, a sheet of dielectric material is inserted between its plates, completely filling the space. The dielectric constant k of this substance is 7.61. Find the voltage V across the capacitor and the charge Qf stored by it after the dielectric is inserted and the circuit has returned to a steady state. V = V Qt = C

A parallel-plate capacitor in air has a plate separation of 1.58 cm and a plate area of 25.0 cm2. The plates are charged to a potential difference of 270 V and disconnected from the source. The capacitor is then immersed in distilled water. Assume the liquid is an insulator. (a) Determine the charge on the plates before and after immersion. before pC pC after (b) Determine the capacitance and potential difference after immersion. Cf = F AV = V (c) Determine the change in energy of the capacitor. nJ Need Help? Read It

Regarding the Earth and a cloud layer 800 m above the Earth as the "plates" of a capacitor, calculate the capacitance. Assume the cloud layer has an area of 1 km2 and that the air between the cloud and the ground is pure and dry. nF   Assume charge builds up on the cloud and on the ground until a uniform electric field of 2.0 106 N/C throughout the space between them makes the air break down and conduct electricity as a lightning bolt. What is the maximum charge the cloud can hold? C