EEE - Parallel Circuits Quiz (or) MCQ

1 .

In an impedance parallel network, the reactive component will ____________ the voltage by 90 degrees.

A)

Lead

B)

Lag

C)

Either lead or lag

D)

Depends on the circuit

Correct Answer : Either lead or lag

Explanation : In an impedance parallel network the reactive component will either lead or lag the voltage by 90 degrees.

2 .

In an impedance parallel network, the reactive component will either lead or lag the voltage by _________ degrees.

A)

180

B)

90

C)

45

D)

0

Correct Answer : 90

Explanation : In an impedance parallel network the reactive component will either lead or lag the voltage by 90 degrees.

3 .

In an impedance parallel network, the reactive component will either lead or lag the ________ by 90 degrees.

A)

Voltage

B)

Current

C)

Either voltage or current

D)

Can't be determined

Correct Answer : Voltage

Explanation : In an impedance parallel network the reactive component will either lead or lag the voltage by 90 degrees.

4 .

Four equal-value resistors are connected in parallel. Ten volts are applied across the parallel circuit and 2 mA are measured from the source. The value of each resistor is

A)

12.5 Ω

B)

20 kΩ

C)

50 Ω

D)

200 Ω

Correct Answer : 20 kΩ

5 .

Five 100 Î© resistors are connected in parallel. If one resistor is removed, the total resistance is

A)

20 Î©

B)

100 Î©

C)

500 Î©

D)

25 Î©

Correct Answer : 25 Î©

6 .

When a 1.6 kÎ© resistor and a 120 Î© resistor are connected in parallel, the total resistance is

A)

Less than 100 Î©

B)

Greater than 1.6 kÎ©

C)

Less than 120 Î© but greater than 100 Î©

D)

Greater than 120 Î© but less than 1.6 kÎ©

Correct Answer : Less than 120 Î© but greater than 100 Î©

7 .

Six resistors are in parallel. The two lowest-value resistors are both 1.2 kÎ©. The total resistance

A)

Is less than 6 kÎ©

B)

Is less than 1.2 kÎ©

C)

Is greater than 1.2 kÎ©

D)

Is less than 600 Î©

Correct Answer : Is less than 600 Î©

8 .

The total resistance of a parallel circuit is 50 Ω. If the total current is 120 mA, the current through the 270 Ω resistor that makes up part of the parallel circuit is approximately

A)

22 mA

B)

50 mA

C)

120 mA

D)

220 mA

Correct Answer : 22 mA

9 .

A set of Christmas tree lights is connected in parallel across a 110 V source. The filament of each light bulb is 1.8 kΩ. The current through each bulb is approximately

A)

18 mA

B)

61 mA

C)

110 mA

D)

610 mA

Correct Answer : 61 mA

10 .

An ammeter has an internal resistance of 50 Ω. The meter movement itself can handle up to 1 mA. If 10 mA is applied to the meter, the shunt resistor, RSH1, is approximately

A)

5.5 Ω

B)

9 Ω

C)

50 Ω

D)

55 Ω

Correct Answer : 5.5 Ω

11 .

In a five-branch parallel circuit, there are 12 mA of current in each branch. If one of the branches opens, the current in each of the other four branches is

A)

0 A

B)

3 mA

C)

12 mA

D)

48 mA

Correct Answer : 12 mA

12 .

Four 8 Ω speakers are connected in parallel to the output of an audio amplifier. If the maximum voltage to the speakers is 12 V, the amplifier must be able to deliver to the speakers

A)

1.5 W

B)

18 W

C)

48 W

D)

72 W

Correct Answer : 72 W

13 .

The power dissipation in each of four parallel branches is 1.2 W. The total power dissipation is

A)

0.3 W

B)

1.2 W

C)

4.8 W

D)

12 W

Correct Answer : 4.8 W

14 .

Three 47 Î© resistors are connected in parallel across a 110 volt source. The current drawn from the source is approximately

A)

2.3 A

B)

7.06 A

C)

47 mA

D)

780 mA

Correct Answer : 7.06 A

15 .

If there are a total of 120 mA into a parallel circuit consisting of three branches, and two of the branch currents are 40 mA and 10 mA, the third branch current is

A)

40 mA

B)

50 mA

C)

70 mA

D)

120 mA

Correct Answer : 70 mA

16 .

A parallel circuit acts as a current divider.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

17 .

The number of current paths equals the number of resistors in parallel.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

18 .

The total current in the given circuit equals _____.

A)

42 mA

B)

86 mA

C)

128 mA

D)

170 mA

Correct Answer : 170 mA

19 .

As additional resistors are connected to a parallel circuit, the total resistance will _________.

A)

increase

B)

decrease

C)

remain unchanged

D)

increase by the value of the resistor being connected

Correct Answer : decrease

20 .

An ammeter is connected in ______ with the branch resistor to measure branch current, and in ______ with the voltage supply to measure total parallel circuit current.

A)

series, series

B)

parallel, series

C)

series, parallel

D)

parallel, parallel

Correct Answer : series, series

21 .

The total current in the given circuit is ________.

A)

0.4 mA

B)

0.6 mA

C)

1.5 mA

D)

2.5 mA

Correct Answer : 2.5 mA

22 .

The reactive component in an impedance parallel circuit leads the voltage when the current _________ the voltage.

A)

Leads

B)

Lags

C)

Either leads or lags

D)

Cannot be determined

Correct Answer : Leads

Explanation : The reactive component in an impedance parallel circuit leads the voltage when the current leads the voltage.

23 .

The active component in an impedance parallel circuit will __________ the voltage.

A)

Lags

B)

Leads

C)

Be in phase with

D)

Either leads or lags

Correct Answer : Be in phase with

Explanation : The active component in an impedance parallel network will always be in phase with the voltage in the circuit.

24 .

The phase difference between the active component of an impedance parallel circuit and the voltage in the network is __________

A)

0

B)

90

C)

180

D)

360

Correct Answer : 0

Explanation : The active component in an impedance parallel network will always be in phase with the voltage in the circuit. Hence the phase difference is 0.

25 .

The quadrature component is also known as?

A)

Active component

B)

Reactive component

C)

Either active or reactive component

D)

Neither active nor reactive component

Correct Answer : Reactive component

Explanation : The quadrature component is also known as the reactive component because the reactive component forms a quadrature with the voltage.

26 .

In a parallel circuit, the branch with the lowest resistance has the most current.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

27 .

A sudden increase in the total current into a parallel circuit may indicate

A)

An open resistor

B)

A drop in source voltage

C)

An increase in source voltage

D)

Either a drop in source voltage or an open resistor

Correct Answer : An increase in source voltage

28 .

There is a total of 800 mA of current into four parallel resistors. The currents through three of the resistors are 40 mA, 70 mA, and 200 mA. The current through the fourth resistor is

A)

0 A

B)

310 mA

C)

490 mA

D)

800 mA

Correct Answer : 490 mA

29 .

Five light bulbs are connected in parallel across 110 V. Each bulb is rated at 200 W. The current through each bulb is approximately

A)

137 mA

B)

9.09 A

C)

2.2 A

D)

1.8 A

Correct Answer : 1.8 A

30 .

A set of Christmas tree lights is connected in parallel across a 110 V source. The filament of each light bulb is 1.8 k. The current through each bulb is approximately

A)

18 mA

B)

61 mA

C)

110 mA

D)

610 mA

Correct Answer : 61 mA

31 .

The sum of the currents into a junction is equal to the sum of the currents out of that junction.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

32 .

In a certain three-branch parallel circuit, R1 has 12 mA through it, R2 has 15 mA through it, and R3 has 25 mA through it. After measuring a total of 27 mA, you can say that

A)

R1 is open

B)

R2 is open

C)

R3 is open

D)

The circuit is operating properly

Correct Answer : R3 is open

33 .

A 470 Ω resistor, a 220 Ω resistor, and a 100 Ω resistor are all in parallel. The total resistance is approximately

A)

30 Ω

B)

60 Ω

C)

470 Ω

D)

790 Ω

Correct Answer : 60 Ω

34 .

Total power in a parallel circuit is found by adding up the power of all the individual resistors.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

35 .

Four resistors are connected in parallel. Fifteen mA flows through resistor R. If the second resistor is 2R, the third resistor 3R, and the fourth resistor 4R, the total current in the circuit is

A)

15 mA

B)

31.25 mA

C)

60 mA

D)

135 mA

Correct Answer : 31.25 mA

36 .

The following currents are measured in the same direction in a three-branch parallel circuit: 200 mA, 340 mA, and 700 mA. The value of the current into the junction of these branches is

A)

1.24 A

B)

200 mA

C)

540 mA

D)

900 mA

Correct Answer : 1.24 A

37 .

The currents into a junction flow along two paths. One current is 4 A and the other is 3 A. The total current out of the junction is

A)

1 A

B)

7 A

C)

Unknown

D)

The larger of the two

Correct Answer : 7 A

38 .

The following resistors are in parallel across a voltage source: 220 Ω, 470 Ω, and 560 Ω. The resistor with the least current is

A)

220 Ω

B)

470 Ω

C)

560 Ω

D)

Impossible to determine without knowing the voltage

Correct Answer : 560 Ω

39 .

Parallel resistors are connected between the same two points.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : True

40 .

If one of the resistors in a parallel circuit is removed, the total resistance

A)

Increases

B)

Decreases

C)

Doubles

D)

Remains the same

Correct Answer : Increases

41 .

When an additional resistor is connected across an existing parallel circuit, the total resistance

A)

Decreases

B)

Remains the same

C)

Decreases by the value of the added resistor

D)

Increases by the value of the added resistor

Correct Answer : Decreases

42 .

If the voltmeter indicates 12 V in the given circuit, the voltage across R2 equals _______.

A)

0 V

B)

12 V

C)

VS minus 12 V

D)

None of the above

Correct Answer : 12 V

43 .

Find the expression for the current I from the given circuit.

A)

I=I_L

B)

I=I_R

C)

I=I_L+I_R

D)

I=0

Correct Answer : I=I_L+I_R

Explaination : I is the total current in the circuit. Since this is a parallel connection, the total current in the circuit is equal to the sum of the currents in each branch of the circuit. Hence I=I_R+I_L.

44 .

Find the value of I_R if I=10A and I_L=8A.

A)

2A

B)

5A

C)

12A

D)

18A

Correct Answer : 2A

Explaination : We know that I=I_R+I_L.
10=I_R+8 => I_R=2A.

45 .

Find the total current if I_L=2A and I_R=8A

A)

-3A

B)

3A

C)

7A

D)

10A

Correct Answer : 10A

Explaination : We know that I=I_R+I_L.
I=8+2=10A.

46 .

The total current divides among parallel resistors in a manner directly proportional to the resistance values.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : False

47 .

Addition of resistors in parallel increases total resistance and decreases total current.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : False

48 .

Three lights are connected in parallel across a 120 volt source. If one light burns out,

A)

The remaining two will not light

B)

The remaining two will glow dimmer

C)

The remaining two will glow brighter

D)

The remaining two will glow with the same brightness as before

Correct Answer : The remaining two will glow with the same brightness as before

49 .

Four resistors of equal value are connected in parallel. If the total voltage is 15 V and the total resistance is 600 Ω, the current through each parallel resistor is

A)

200 mA

B)

100 mA

C)

6.25 mA

D)

25 mA

Correct Answer : 6.25 mA

50 .

The total resistance for two resistors in parallel is equal to the sum of the two resistors.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : False

51 .

When an open circuit occurs in a parallel branch, the total resistance decreases.

A)

True

B)

False

C)

Can Not Say

D)

None of the above

Correct Answer : False

52 .

An open resistor in parallel will cause the total ___ to increase.

A)

power

B)

voltage

C)

current

D)

resistance

Correct Answer : resistance

53 .

Circuit analysis should reveal that the largest resistance in a parallel circuit has the __________.

A)

least current

B)

most current

C)

least voltage

D)

most voltage

Correct Answer : least current

54 .

An ammeter is connected in ______ with the branch resistor to measure branch current, and in ______ with the voltage supply to measure total parallel circuit current.

A)

parallel, series

B)

series, parallel

C)

series, series

D)

parallel, parallel

Correct Answer : series, series

55 .

The total resistance in the given circuit is _____.

A)

greater than 8Ω

B)

greater than 30Ω

C)

4.8Ω

D)

58Ω

Correct Answer : 4.8Ω

56 .

The total power in the given circuit is ________.

A)

4.8 mW

B)

7.2 mW

C)

18 mW

D)

30 mW

Correct Answer : 30 mW

57 .

A circuit is parallel between two points if ______ between those two points.

A)

the voltage divides

B)

all resistors are equal

C)

there is only one current path

D)

more than one current path exists

Correct Answer : more than one current path exists

58 .

A parallel resistor's value that changes with age will cause a corresponding change in ______ .

A)

branch current

B)

branch voltage

C)

power supply voltage

D)

both branch current and branch voltage

Correct Answer : branch current

59 .

If R₂ opens in the given circuit, the voltage across R₁ will ___.

A)

increase

B)

decrease

C)

equal 0 V

D)

remain unchanged

Correct Answer : remain unchanged

60 .

If R₁ opens in the given circuit, the total current equals _______.

A)

42 mA

B)

86 mA

C)

128 mA

D)

170 mA

Correct Answer : 128 mA