A 2.0-cm-diameter circular parallel plate capacitor with a spacing of 0.5 mm is charged to 200 V. Assume the medium between the two parallel plats is a vacuum. a) What is the total energy stored in the electric field? b) What is the energy density?

Two thin plates (0.50 m x 0.50 m x 'very thin') of a parallel capacitor are located parallel to the xzplane. One of the large plates crosses the y-axis at y = 0 cm, and the other crosses at y = -1 cm. The charge on the positive plate is +30 nC, and on the negative plate, -30 nC. a) What is the voltage from the positive plate to the negative plate? b) What is the electric potential difference from the negative plate to a point in the middle of the space between the plates? c) If the electric potential at the negative plate is 100 V, what is the electric potential at the positive plate? ( d-f) The negative plate is now shifted 0.5 cm away from the positive plate. d) What is the voltage from the positive to the negative plate? ( e-f) If an electron is released from rest from very close to the negative plate, and it flies to the positive plate, e) what is the electron's change in potential energy? f) what is the electron's speed when it hits the positive plate?

T or F? a. For a parallel plate capacitor, the capacitance depends on the area of the plates and on the separation distance between the plates, it does not depend on the material the plates are made of. b. If a conductor is placed in an electric field, and is in electrostatic equilibrium, the electric field lines just inside the conductor will be parallel to its surface.

Two large parallel plates are separated by a 0.015-m gap. The plates are connected to the terminals of a 12-V battery, which remains connected. a) What is the strength of the electric field in the region between the plates? b) What happens to the strength of the electric field if the gap between the plates is reduced to 0.010 m? Justify your answer. c) Does charge flow through the battery as the separation between the plates is being reduced? Explain your answer.