PHYS-2326: University Physics-II
HOMEWORK PROBLEMS
Ch-26
Chapter 26:
Khalid Bukhari
CAPACITANCE AND DIELECTRICS
Show the equations and calculations, and box your answer. Be sure to include the units.
NOTE: Any four questions from this HW will be graded, and the marks for this HW will be based on these
only. (1, 2, 4, 6, 13, 18, 19, 31, 45)
1. How much charge is on each plate of a 4.00-F capacitor when it is connected to a 12.0-V battery?
(b) If this same capacitor is connected to a 1.50-V battery, what charge is stored?
2. Two conductors having net charges of +10.0 C and –10.0 C have a potential difference of 10.0 V
between them. (a) Determine the capacitance of the system. (b) What is the potential difference
between the two conductors if the charges on each are increased to +100 C and –100 C?
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An air-filled parallel-plate capacitor has plates of area 2.30 cm2 separated by 1.50 mm. (a) Find the
value of its capacitance. The capacitor is connected to a 12.0-V battery. (b) What is the charge on the
capacitor? (c) What is the magnitude of the uniform electric field between the plates?
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PHYS-2326: University Physics-II
6.
Ch-26
Khalid Bukhari
(a) Regarding the Earth and a cloud layer 800 m above the Earth as the “plates” of a capacitor,
calculate the capacitance of the Earth–cloud layer system. Assume the cloud layer has an area of
1.00 km2 and the air between the cloud and the ground is pure and dry. Assume charge builds up on
the cloud and on the ground until a uniform electric field of 3.00 × 106 N/C throughout the space
between them makes the air break down and conduct electricity as a lightning bolt. (b) What is the
maximum charge the cloud can hold?
13. Two capacitors, C1 = 5.00 F and C2 = 12.0 F, are connected in parallel, and the resulting
combination is connected to a 9.00-V battery. Find (a) the equivalent capacitance of the
combination, (b) the potential difference across each capacitor, and (c) the charge stored on each
capacitor.
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PHYS-2326: University Physics-II
Ch-26
Khalid Bukhari
18. Find (a) the equivalent capacitance of the capacitors in Figure P26.18,
(b) the charge on each capacitor, and (c) the potential difference across
each capacitor.
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PHYS-2326: University Physics-II
Ch-26
Khalid Bukhari
19. For the system of four capacitors shown in Figure P26.19, find (a) the
equivalent capacitance of the system, (b) the charge on each capacitor,
and (c) the potential difference across each capacitor.
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PHYS-2326: University Physics-II
Ch-26
Khalid Bukhari
31. A 12.0-V battery is connected to a capacitor, resulting in 54.0 C of charge stored on the capacitor.
How much energy is stored in the capacitor?
45. Determine (a) the capacitance and (b) the maximum potential difference that can be applied to a
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Teflon-filled parallel-plate capacitor having a plate area of 1.75 cm and a plate separation of 0.0400
mm.
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