Multiple Choice Quiz: Passive Circuits

In the circuit shown, the output waveform will have:

(a) a square shape
(b) a triangle shape
(c) a series of narrow pulses

In the circuit shown, the output waveform will have:

(a) a square shape
(b) a triangle shape
(c) a series of narrow pulses

A C-R discharging circuit consists of C=100µF and R=2 MΩ. If the capacitor is initially charged to a voltage of 40 V, which one of the following gives the time taken for the capacitor voltage to fall to 12.6 V?

(a) 100 s
(b) 200 s
(c) 400 s

A C-R circuit consists of C=100µF and R=100kΩ. Which one of the following gives the time constant of the circuit?

(a) 1 s
(b) 10 s
(c) 100 s

A C-R discharging circuit consists of C=1µF and R=1MΩ. If the capacitor is initially charged to a voltage of 20 V, which one of the following gives the time taken for the capacitor voltage to fall to 6.3 V?

(a) 1 s
(b) 2 s
(c) 20 s

Which one of the following gives the value of the unknown current shown in the figure?

(a) 25 mA
(b) 35 mA
(c) 40 mA

The graph of capacitor voltage plotted against time for a C-R charging circuit has a shape that indicates:

(a) a straight line
(b) exponential decay
(c) exponential growth

Which one of the following C-R combinations has a time constant of 40 ms?

(a) 4 kΩ and 10 nF
(b) 20 kΩ and 2 µF
(c) 80 MΩ and 2 nF

A C-R charging circuit consists of C=1µF and R=1MΩ. If the circuit is supplied with a voltage of 10 V and the capacitor is initially fully discharged, which one of the following gives the capacitor voltage after a time of 1 s?

(a) 3.15 V
(b) 6.3 V
(c) 10 V

The voltage produced by the circuit shown will be:

(a) 3 V
(b) 10 V
(c) 12 V

Which one of the following gives the value of the unknown voltage shown in the figure?

(a) 0.5 V
(b) 1.5 V
(c) 2 V

Which one of the following gives the value of the unknown current shown in the figure?

(a) 800 mA
(b) 1.2 A
(c) 1.4 A

Which one of the following statements is TRUE for a C-R discharging circuit?

(a) The capacitor voltage will reach zero in a time interval equal to the time constant
(b) The capacitor voltage will reach zero in a time interval equal to twice the time constant
(c) The capacitor voltage will never reach zero

Which one of the following gives the value of the unknown current shown in the figure?

(a) 0.8 A
(b) 1 A
(c) 2 A

A C-R charging circuit is to have a time constant of 0.2 s. If a 200 nF capacitor is available, what value of resistor is required?

(a) 1 kΩ
(b) 100 kΩ
(c) 1 MΩ

The graph of capacitor voltage plotted against time for a C-R discharging circuit has a shape that indicates:

(a) a straight line
(b) exponential decay
(c) exponential growth

Which one of the following gives the value of the unknown voltage shown in the figure?

(a) 1 V
(b) 5 V
(c) 8 V

Which one of the following statements is TRUE for a C-R charging circuit?

(a) The capacitor voltage will be the same as the input voltage after a time interval equal to the time constant
(b) The capacitor voltage will be the same as the input voltage after a time
(c) The capacitor voltage will never quite reach the input voltage

Which one of the following gives the value of the unknown voltage shown in the figure?

(a) 6 V
(b) 9 V
(c) 15 V

A C-R charging circuit consists of C=10µF and R=20 kΩ. If the circuit is supplied with a voltage of 5 V and the capacitor is initially fully discharged, which one of the following gives the time taken for the capacitor voltage to reach 3.15 V?

(a) 0.2 s
(b) 0.4 s
(c) 0.5 s

In the circuit shown, where R1 and R2 have different values

(a) the same current will flow in both resistors
(b) the same voltage will appear across both resistors
(c) the same power will be dissipated in both resistors

In the circuit shown, where R1 and R2 have different values:

(a) the same current will flow in both resistors
(b) the same voltage will appear across both resistors
(c) the same power will be dissipated in both resistors

Which one of the following statements is TRUE for a C-R charging circuit?

(a) The capacitor voltage will reach the supply voltage in a time interval equal to the time constant
(b) The capacitor voltage will reach the supply voltage in a time interval equal to twice the time constant
(c) The capacitor voltage will never reach the supply voltage

Which one of the following statements is TRUE for a C-R discharging circuit?

(a) The capacitor voltage will be zero after a time interval equal to the time constant
(b) The capacitor voltage will be zero after a time interval equal to five times the time constant
(c) The capacitor voltage will never quite reach zero

The circuit shown is:

(a) a potential divider
(b) a tuned circuit
(c) a waveshaping circuit