| A | B |
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| The two plates of a capacitor hold +2500 microcoulombs and -2500 microcoulombs of charge, respectively, when the potential difference is 950 V. What is the capacitance? | 2.63 x 10^-6 F or 2.63 microfarads |
| The potential difference between two parallel wires in air is 120 V. They carry equal and opposite charge of magnitude 95 pC. What is the capacitance of the two wires? | 7.9 x 10^-13 F or 0.79 pF |
| A 7500-pF capacitor holds 16.5 x 10^-8 C of charge. What is the voltage across the capacitor? | 22 V |
| How much charge flows from a 12.0-V battery when it is connected to a 9.00-microfarad capacitor? | 1.08 x 10^-4 C or 108 microfarads |
| A 0.20-F capacitor is desired. What area must the plates have if they are to be separated by a 2.2-mm air gap? | 4.97 x 10^7 m^2 |
| An electric field of 8.50 x 10^5 V/m is desired between two parallel plates each of area 35.0 cm^2 and separated by 2.45 mm of air. What charge must be on each plate? | 2.63 x 10^-8 C |
| 550 V is applied to a 7200-pF capacitor. How much energy is stored? | 1.089 x 10^-3 J |
| A cardiac defibrilator is used to shock a heart that is beating erratically. A capacitor in this device is charged to 6000 V and stores 200 J of energy. What is its capacitance? | 1.11 x 10^-5 F or 11.1 microfarads |
