Download Multiple Choice MC1:You connect three capacitors as shown in the

Multiple Choice
MC1:You connect three capacitors as shown in the diagram below. If the potential difference between A and B is 24.5
V, what is the total energy stored in this system of capacitors if C1 = 5.0 µF, C2 = 4.0 µF, and C3 = 3.0 µF?
A) 1.7 ◊ 10–4 J B) 1.5 ◊ 10–4 J C) 2.2 ◊ 10–5 J *D) 6.8 ◊ 10–4 J E) 4.0 ◊ 10–4 J
MC2: The capacitance of a parallel-plate capacitor is 24 mF when the plates are separated by a material of dielectric
constant 2.0. If this material is removed, leaving air between the plates, and the separation between the plates is
tripled, the capacitance is
A) unchanged B) 16 mF C) 36 mF D) 0.14 mF *E) 4.0 mF
MC3:In the circuit below, the current I through the battery is approximately
*A) 1.7 A B) 4.4 A C) 0.36 A D) 0.60 A E) 3.4 A
MC4:Three identical light bulbs are connected in parallel to a constant voltage power supply. Initially, switch S1 is
closed and the other two switches open. When the other two switches, S2 and S3, are closed, the brightness of the
first light bulb
A) is dimmer. B) depends on how long the switches are on. *C) is unchanged. D) Insufficient information to tell since
V and R are not given. E) is brighter.
MC5:Which of the following relations among the quantities in the figure below is generally correct?
A) I1 R1 = I2 R2 B) I3 R4 = I4 R3 *C) I3 R3 = I4 R4 D) I1 R1 + I2 R2 = Á E) I1 R1 = I4 R4
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Problem 1 (12 pts):A parallel combination of two identical 2.00-mF parallel-plate capacitors (no dielectric is in the
space between the plates) is connected to a 100-V battery. The battery is then removed and the separation between
the plates of one of the capacitors is doubled. Find the charge on the positively charged plate of each of the capacitors.
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Problem 2 (12 pts): In the circuit shown below, the capacitor has a capacitance of 2.50 mF and the resistor has a
resistance of 0.500 MW. Before the switch is closed, the potential drop across the capacitor is 12.0 V, as shown. Switch
S is closed at t = 0. (a) What is the current immediately after switch S is closed? (b) At what time t is the voltage
across the capacitor 24.0 V?
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