During a lightning discharge, charges amounting to 30C move through a potential difference of 1.0 x 10^8 V in 2.0 x 10^(−2) s. What is the power released by this lightning bolt? *   A. 1, 500 W. B. 3.3 x 10^6 W. C. 6.0 x 10^7 W. D. 3.0 x 10^9 W. E. 1.5 x 10^11 W.

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A capacitor (10.0 µF) is connected to a power supply and charged to 120 V, then disconnected to the power supply. Switch S is open. A) What is the charge Q[0] on 10.0-µF capacitor. B) What is the energy stored in the 10.0-µF capacitor? C) A 5.0-µF is initially uncharged. We close switch S. After charge no longer flows, what is the potential difference across each capacitor? D) What is the final energy of the system?

4. An 8400 pF air-gap capacitor is charged by a power supply set to 9.1 V. It is removed from the power supply, and then a layer of mica (dielectric constant of 7) is inserted between the plates. a. What is the new capacitance of the plates? b. Consider just charge on the plates and the voltage across the plates. Which of them is the same before and after the mica is inserted? Why? c. Find the new value for the one that changed. d. Did the electric field increase, decrease, or stay the same when the mica was inserted? Explain how you know. e. Calculate the new potential energy stored by the capacitor. [5x10-8 J]

At a distance r from a point charge the electric potential is V. If the distance increased to 3r, the electric potential becomes O a. 3V b. V/9 c. 9V O d. V/3

A parallel-plate capacitor stores charge Q. The capacitor is then disconnected from its voltage source, and the space between the plates is filled with a dielectric of constant κ = 2. What is the relationship between the stored energies of the capacitor, where PEi is the initial stored energy, and PEf is the stored energy after the dielectric is inserted? a. PEf = 0.25PEi b. PEf = 0.5PEi c. PEf = PEid. PEf = 2PEi

Given an electric field that points downward. When a negative charge moves upward in this field   Question 3 options:   the field does zero work on it and the potential energy does not change.   the field does negative work on it and the potential energy decreases.   the field does positive work on it and the potential energy decreases.   the field does positive work on it and the potential energy increases.   the field does negative work on it and the potential energy increases.

It takes 112 J of work to move 2.3 C of charge from the negative plate to the positive plate of a parallel plate capacitor. What voltage difference exists between the plates? Answer in units of V.

A parallel-plate capacitor has square plates of side length s and distance d between them. It stores energy U when it is connected across a fixed potential difference V. In order to decrease by a factor of 4 the amount of energy stored in this capacity will still connected to the potential difference V, the lengths that should be changed to...? A. 4s B. S/2 C. 8s D. 2s E. S/4

3. A 3.00 - uF capacitor and a 6.00 - µF capacitor are discharged and then connected in series, and the series combination is then connected in parallel with an 8.00 - µF capacitor. Diagram this combination. What is the equivalent capacitance of this combination?