Deck 4: Series Circuits

Question 1

A series circuit has multiple current paths.

Answer 1

False

Question 2

Calculate PR2 in Figure 4 -1 if VR1 =16 V, R1 = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ.

A)25.6 mW
B)2.56 mW
C)0.0256 mW
D)0.256 mW

Answer 2

25.6 mW

Question 3

If 4.7 kΩ, 2.2 kΩ and 1.2 kΩ resistors are wired in series, the total resistance is 8.7 kΩ.

Answer 3

False

Question 4

If a resistor is rated at 1/2 W, it can safely dissipate 0.325 W.

Question 5

In a series circuit, the current is the same at every point in the circuit.

Question 6

Calculate VR2 and VR3 in Figure 4 -1 if VR1 = 16 V, R1 = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ.

A)VR2 = 16 V, VR3 = 16 V
B)VR2 = 16 V, VR3 = 12 V
C)VR2 = 24 V, VR3 = 12 V
D)VR2 = 16 V, VR3 = 24 V

Question 7

Total power dissipated in a series circuit equals source voltage multiplied by current.

Question 8

Voltage sources in series increase both voltage and current capacity.

Question 9

The total power dissipated in a series circuit equals the sum of the individual powers.

Question 10

According to Kirchhoff's Voltage Law, the sum of the individual voltage drops in a series circuit equals the source voltage.

Question 11

If 6.8 kΩ, 1.2 kΩ and 5.6 kΩ resistors are wired in series, the total resistance is 13.6 kΩ.

Question 12

Calculate the current in Figure 4 -1 if VR1 = 16 V, R1 = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ.

A)1.6 mA
B)12 mA
C)3.2 mA
D)0 A

Question 13

Kirchhoff's Voltage Law states that the algebraic sum of all the voltages around a closed path is zero.

Question 14

Calculating current for a series resistor circuit can be accomplished with a measured voltage across one of the resistors divided by that resistor's value.

Question 15

If a resistor is dissipating 1/4 W, it can supply 1/4 W to the load.

Question 16

What is the total resistance in Figure 4 -1 if R1 = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ?

A)0 kΩ
B)25 kΩ
C)35 kΩ
D)infinite Ω

Question 17

If a 1/4 W resistor and a 1/2 W resistor are wired in series, they can safely dissipate 3/4 W.

Question 18

Calculate VT in Figure 4 -1 if VR1 = 16 V, R1 = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ.

A)112 V
B)24 V
C)56 V
D)16 V

Question 19

Three 2 V cells in series with one in series -opposing would yield 2 V.

Question 20

The voltage produced by a single solar cell is

A)18 V
B)24 V
C)0.5 V
D)0.7 V

Question 21

There is a type of analog -to -digital converter that uses a voltage divider string to perform the conversion. This type of ADC is called

A)s series converter
B)a sigma -delta converter
C)a flash converter
D)all of the above

Question 22

Calculate VT in Figure 4 -1 if R1 = 4.7 kΩ, VR1 = 10 V, R2 = 4.7 kΩ and R3 = 4.7 kΩ.

A)14.7 V
B)10 V
C)4.7 V
D)30 V

Question 23

A 22 kΩ and 12 kΩ resistor are connected across a 68 V source. How is the voltage divided?

A)22 V and 12 V
B)34 V and 34 V
C)68 V and 68 V
D)44 V and 24 V

Question 24

If R2 shorts in Figure 4 -1, the total circuit power .

A)increases
B)remains the same
C)depends upon the source voltage
D)decreases

Question 25

Based upon electron current flow, the polarity on the side of the resistor where current enters is . The polarity on the side of the resistor where current exits is .

A)positive, positive
B)negative, positive
C)negative, negative
D)positive, negative

Question 26

R1 = 4.7 kΩ, R2 = 4.7 kΩ and R3 = 4.7 kΩ in Figure 4 -1. What is RT if R2 shorts?

A)4.7 kΩ
B)0 Ω
C)9.4 kΩ
D)infinite Ω

Question 27

Calculate IT in Figure 4 -1 if R1 = 4.7 kΩ, VR1 = 10 V, R2 = 4.7 kΩ and R3 = 4.7 kΩ.

A)6 mA
B)1 mA
C)4.26 mA
D)2.13 mA

Question 28

Calculate PT in Figure 4 -1 if VT = 100 V and all three resistors are each 47 kΩ.

A)22 W
B)709 mW
C)23.6 mW
D)70.9 mW

Question 29

When 50 V is applied to four series resistors, 100 µA flows. If R1 = 12 kΩ, R2 = 47 kΩ and R3 = 56 k Ω, what is the value of R4?

A)38.5 kΩ
B)3.85 kΩ
C)3.85 MΩ
D)385 kΩ

Question 30

Calculate VR3 in Figure 4 -1 if VT = 50 V, VR1 = 19.7 V and VR2 = 2.7 V.

A)47.3 V
B)22.4 V
C)27.6 V
D)30.3 V

Question 31

If R1 = 12 kΩ and R2 = 5 kΩ and they are wired in series across a 20 V source, what is VR1 and VR2?

A)VR1 = 0 V, VR2 = 20 V
B)VR1 = 10 V, VR2 = 10 V
C)VR1 = 14.12 V, VR2 = 5.88 V
D)VR1 = 5.88 V, VR2 = 14.12 V

Question 32

A 500 kΩ potentiometer is connected across a 5 V source. If the voltage from the wiper to the lower end of the potentiometer is 1.2 V, what is the resistance of that lower part?

A)500 kΩ
B)0 Ω
C)120 kΩ
D)380 kΩ

Question 33

How much voltage is dropped across R2 and R3 in Figure 4 -1 if R1 = 4.7 kΩ, VR1 = 10 V, R2 = 4.7 kΩ and R3 = 4.7 kΩ?

A)VR2 = 4.7 V, VR3 = 10 V
B)VR2 = 10 V, VR3 = 4.7 V
C)VR2 = 10 V, VR3 = 10 V
D)VR2 = 14.7 V, VR3 = 14.7 V

Question 34

Two 100 kΩ resistors are wired in series across a 20 V source. How much voltage does each resistor drop?

A)100 kΩ
B)10 V
C)20 V
D)100 mA

Question 35

What is the total supply voltage if 16 V and 12 V sources are wired in series opposing?

A)28 V
B)12 V
C)4 V
D)16 V

Question 36

Four resistors are connected in series across an 18 V source. Three resistors drop 0 V and one resistor drops 18 V. What's the trouble?

A)Two of the resistors are shorted.
B)One resistor is open.
C)The three resistors are open.
D)There is no trouble; these voltages are normal.

Question 37

VR1 = 16 V, Rµ = 10 kΩ, R2 = 10 kΩ and R3 = 15 kΩ in Figure 4 -1. If R2 opens, then RT is .

A)0 Ω
B)10 kΩ
C)25 kΩ
D)infinite Ω

Question 38

If 12 V and 17 V sources are wired in series aiding, what is the total supply voltage?

A)17 V
B)5 V
C)12 V
D)29 V

Question 39

If 12 V and -19 V sources are connected so their total voltage is -7 V, they are .

A)series aiding
B)in parallel
C)series opposing
D)connected dangerously

Question 40

If R2 opens in Figure 4 -1, the total power dissipated .

A)increases to maximum
B)will depend upon the source voltage
C)decreases to zero
D)remains the same

Question 41

If a 4.7 kΩ, 5.6 kΩ and 10 kΩ resistor are in series, which resistor drops the most voltage?

A)the 10 kΩ resistor
B)the 4.7 kΩ resistor
C)the 5.6 kΩ resistor
D)That can't be determined from the given information.

Question 42

If 5 V and 16 V power supplies are connected in series aiding, what is the total voltage?

A)24 V
B)80 V
C)21 V
D)16 V

Question 43

The voltage drop across any resistor or combination of resistors in a series circuit equals:

A)the applied voltage across the resistor (A).
B)the product of the circuit current times the resistance value.
C)the ratio of the resistance values to the total resistance times the source voltage.
D)all of these.

Question 44

In a series circuit, total power PT is calculated as:

A)P1 + P2 + P3 + etc.
B)P1 ÷ P2 ÷ P3 ÷ etc.
C)1/P1 + 1/P2 + 1/P3 + etc.
D)P1 × P2 × P3 × etc.

Question 45

If five equal resistors dissipate a total of 10 W in a series circuit, how much power does each resistor dissipate?

A)10 W
B)2 W
C)50 W
D)5 W

Question 46

If a 100 Ω, 220 Ω, and 330 Ω resistor are connected in series, total resistance equals .

A)650 Ω
B)less than 100 Ω
C)the average of the three values
D)1650 Ω

Question 47

If -12 V and -6 V are connected so they equal -18 V, these sources are .

A)series opposing
B)connected dangerously
C)in parallel
D)series aiding

Question 48

One of the most popular applications of a potentiometer is as an adjustable voltage divider also known as a:

A)voltage control.
B)divider control.
C)current control.
D)volume control.

Question 49

Three resistors are connected in series across a 60 V source. If VR1 = 19 V and VR2 = 14.3 V, then what is the voltage drop across R3?

A)45.7 V
B)19 V
C)14.3 V
D)26.7 V

Question 50

A 50 kΩ potentiometer is connected across a 15 V source. If the voltage from the wiper to the lower end of the potentiometer is 3.2 V, what is the resistance of that lower part?

A)50 kΩ
B)10.7 kΩ
C)0 Ω
D)39.3 kΩ

Question 51

If a 10 kΩ and 5 kΩ resistor are connected in series across a 12 V source, the voltage across the 10 k Ω resistor is and the voltage across the 5 kΩ resistor is .

A)8 V, 4 V
B)4 V, 8 V
C)4 V, 4 V
D)8 V, 8 V

Question 52

Two resistors are in series across a 12 V source. If each resistor equals 470 kΩ, what is the voltage across each resistor?

A)6 V
B)12 V
C)3 V
D)9 V

Question 53

If three 2.2 kΩ resistors are connected in series across a 50 V source, PT equals .

A)52.08 mW
B)379 mW
C)402 mW
D)104.2 mW

Question 54

If each of the six resistors in a series circuit drops 5 V, the source voltage .

A)equals 5 V
B)depends on the current
C)depends on the resistor values
D)equals 30 V

Question 55

Circuit ground or chassis ground can be thought of as a:

A)reference point.
B)common point.
C)neutral connection point.
D)all of these

Question 56

Four series resistors are connected across a 30 V source and carry 0.125 mA. If R1 = 10 kΩ, R2 = 33 kΩ and R3 = 47 kΩ, what is the value of R4?

A)150 Ω
B)1.5 kΩ
C)150 kΩ
D)15 kΩ

Question 57

In a series circuit, the largest amount of power is dissipated by:

A)the smallest resistor.
B)the first resistor.
C)the largest resistor.
D)any resistor, since the current is the same throughout the circuit.

Question 58

If a 68 Ω, 33 Ω, 100 Ω and 47 Ω resistor are connected in series across a 9 V battery, the current equals .

A)27.6 A
B)22.3 mA
C)36.3 mA
D)327 mA

Question 59

If 18 V and 6 V sources are connected in series opposing, what is the total voltage?

A)12 V
B)6 V
C)18 V
D)2 V

Question 60

-1.2 V, +5 V and +6 V batteries are connected in series. The total voltage is .

A)12.2 V
B)1.3 V
C)1.2 V
D)9.8 V

Question 61

Voltage B to ground is less than normal. What could be the cause of failure?

A)open between B and C
B)open between C and D
C)short between E and D
D)short between A and B

Question 62

A short in a series circuit results in:

A)decreased or reduced current flow.
B)decreased power consumption.
C)increased circuit resistance.
D)increased or maximum current flow.

Question 63

An open in a series circuit results in:

A)source voltage appearing across the open.
B)no current flow.
C)no power dissipation.
D)all of these.

Question 64

What type of resistor could be used as variable voltage -divider?

A)thermistor
B)rheostat
C)potentiometer
D)any one of the above

Question 65

The resistor between points E and D looks charred. What most likely would cause this?

A)open A and the power supply
B)short between A and B
C)short between A and D
D)Any of these could cause this problem.

Question 66

What is the easiest, most practical measurement performed during troubleshooting?

A)voltage
B)current
C)power
D)resistance

Question 67

Voltage from C to ground is 100 V. What is the probable cause of failure?

A)open between A and B
B)open between E and D
C)short between A and B
D)voltage reading is normal