Electronic Components Practice Questions — Armed Services Vocational Aptitude Battery (ASVAB) — Page 11

Question 201Question →

Standard four-band carbon composition and film resistors use color-coded bands to indicate their nominal resistance values and tolerances. Match each four-band resistor color code sequence on the left to its corresponding nominal resistance value on the right.

Click a left item, then click its matching right item

Show answer & explanation

Answer

Orange, Orange, Brown, Gold pairs with

330\ \Omega \pm 5\%

; Brown, Black, Red, Gold pairs with

1.0\text{ k}\Omega \pm 5\%

; Yellow, Violet, Orange, Gold pairs with

47\text{ k}\Omega \pm 5\%

; and Green, Blue, Yellow, Gold pairs with

560\text{ k}\Omega \pm 5\%

.

Each resistor color code sequence maps to its nominal value by combining the first two color values as base digits and multiplying by ten raised to the value of the third color: Orange-Orange-Brown gives

33 \times 10^1 = 330\ \Omega

; Brown-Black-Red gives

10 \times 10^2 = 1.0\text{ k}\Omega

; Yellow-Violet-Orange gives

47 \times 10^3 = 47\text{ k}\Omega

; and Green-Blue-Yellow gives

56 \times 10^4 = 560\text{ k}\Omega

. All fourth bands are Gold, representing a

\pm 5\%

tolerance.

Step-by-Step Solution

1

Decode the significant digits for each color sequence using the standard EIA color code chart.

Orange-Orange is

33

, Brown-Black is

10

, Yellow-Violet is

47

, and Green-Blue is

56

.

In a standard four-band resistor, the first two bands always represent the first and second significant digits.

2

Determine the power-of-ten multiplier from the third band and apply metric prefixes.

Brown multiplier is

10^1

(

33 \times 10 = 330\ \Omega

); Red multiplier is

10^2

(

10 \times 100 = 1.0\text{ k}\Omega

); Orange multiplier is

10^3

(

47 \times 1,000 = 47\text{ k}\Omega

); Yellow multiplier is

10^4

(

56 \times 10,000 = 560\text{ k}\Omega

).

The third color band represents the number of trailing zeros (the multiplier

10^n

).

3

Identify the tolerance rating from the fourth band.

All four sequences end in Gold, which corresponds to

\pm 5\%

.

Gold in the fourth position designates a standard

\pm 5\%

manufacturing tolerance.

Key Concept

Four-band resistor color code decoding and metric unit conversion

Estimated Time:1m 0s

Question 202Question →

A four-band resistor removed from an amplifier circuit displays the color band sequence Yellow, Violet, Red, and Gold. When measured with an ohmmeter, which range represents the acceptable resistance values for this component to be within manufacturer tolerance?

4,230\ \Omega\text{ to }5,170\ \Omega

446.5\ \Omega\text{ to }493.5\ \Omega

4,465\ \Omega\text{ to }4,935\ \Omega

4,653\ \Omega\text{ to }4,747\ \Omega

Show answer & explanation

Answer: $4,465\ \Omega\text{ to }4,935\ \Omega$

Answer

The acceptable tolerance range is

4,465\ \Omega\text{ to }4,935\ \Omega

.

Decoding the four bands gives Yellow (4), Violet (7), Red (multiplier of

100

), and Gold (

\pm 5\%

tolerance). The nominal resistance is

47 \times 100 = 4,700\ \Omega

. Five percent of

4,700\ \Omega

is

235\ \Omega

. Subtracting and adding

235\ \Omega

to the nominal value yields the valid range of

4,465\ \Omega\text{ to }4,935\ \Omega

.

Step-by-Step Solution

1

Decode the significant digits and multiplier from the first three color bands.

Yellow = 4, Violet = 7, Red =

\times 10^2

(

100

). Nominal resistance =

47 \times 100 = 4,700\ \Omega

.

The standard EIA four-band color code uses the first two bands for significant digits and the third band as a decimal multiplier.

2

Determine the tolerance percentage from the fourth band.

Gold =

\pm 5\%

.

The fourth band specifies the manufacturing tolerance rating.

3

Calculate the allowable deviation in ohms.

4,700\ \Omega \times 0.05 = 235\ \Omega

.

Multiplying the nominal resistance by the tolerance percentage gives the maximum allowable variation.

4

Calculate the lower and upper limits of acceptable resistance.

Lower Limit:

4,700\ \Omega - 235\ \Omega = 4,465\ \Omega

; Upper Limit:

4,700\ \Omega + 235\ \Omega = 4,935\ \Omega

.

Adding and subtracting the allowable deviation establishes the operational boundaries.

Key Concept

Four-band resistor color code decoding and percentage tolerance range calculation

Estimated Time:45s

Question 203Question →

A carbon-film resistor has four distinct color bands in sequence: Red, Violet, Orange, and Gold. What is the minimum acceptable resistance of this resistor in kilohms ( $\text{k}\Omega$ ) based on its color code and tolerance rating?

Show answer & explanation

Answer: 25.65

Answer

The minimum acceptable resistance is 25.65 kilohms (kΩ).

According to the standard EIA 4-band resistor color code, Red = 2, Violet = 7, Orange = multiplier 10^3 (1,000), and Gold = ±5% tolerance. The nominal resistance is 27 × 1,000 Ω = 27,000 Ω = 27 kΩ. The allowable variation is 5% of 27 kΩ, which is 1.35 kΩ. Subtracting this from the nominal value gives a minimum acceptable resistance of 27 kΩ - 1.35 kΩ = 25.65 kΩ.

Step-by-Step Solution

1

Identify the significant digits from the first two color bands.

Red represents 2 and Violet represents 7, forming the base number 27.

In standard 4-band resistor color codes, the first two bands represent the first two significant figures.

2

Apply the decimal multiplier from the third color band and convert to kilohms.

Orange represents a multiplier of 10^3 (1,000), giving a nominal value of 27 × 1,000 Ω = 27,000 Ω = 27 kΩ.

The third band indicates the power of ten by which the significant digits are multiplied.

3

Calculate the tolerance value based on the fourth band.

Gold indicates a ±5% tolerance. 5% of 27 kΩ is 0.05 × 27 kΩ = 1.35 kΩ.

The fourth band specifies the allowable percentage deviation from the nominal resistance value.

4

Compute the lower limit of the allowable resistance range.

27 kΩ - 1.35 kΩ = 25.65 kΩ.

The minimum acceptable value is obtained by subtracting the allowable tolerance from the nominal resistance.

Key Concept

Four-Band Resistor Color Code and Tolerance Calculation

Alternative Method

Calculate the minimum multiplier directly: 27 kΩ × (1 - 0.05) = 27 kΩ × 0.95 = 25.65 kΩ.

Estimated Time:45s

Question 204Question →

An electronics technician needs to replace a damaged component on a circuit board with an $820\ \Omega$ resistor having a $\pm 5\%$ tolerance. Which four-band color code sequence identifies the correct replacement resistor?

Gray, Red, Black, Gold

Gray, Red, Brown, Gold

Gray, Red, Red, Gold

Red, Gray, Brown, Gold

Show answer & explanation

Answer: Gray, Red, Brown, Gold

Answer

Gray, Red, Brown, Gold

The color band sequence Gray, Red, Brown, Gold translates directly to

8

(Gray),

2

(Red),

\times 10^1

(Brown), and

\pm 5\%

(Gold). Multiplying the significant digits

82

by

10

yields exactly

820\ \Omega

with a

\pm 5\%

tolerance.

Step-by-Step Solution

1

Determine the first two significant digits from the target resistance value.

The first digit is

8

(Gray) and the second digit is

2

(Red).

Standard four-band resistors use the first two bands to represent significant numerical digits.

2

Calculate the multiplier needed to obtain

820\ \Omega

from the significant digits

82

.

82 \times 10^1 = 820\ \Omega

, which corresponds to the multiplier color Brown.

The third band represents the power of ten multiplier (

10^1 = 10

, which is Brown).

3

Identify the tolerance band corresponding to

\pm 5\%

.

A

\pm 5\%

tolerance is denoted by Gold.

The fourth band indicates manufacturing tolerance, where Gold designates

\pm 5\%

and Silver designates

\pm 10\%

.

Key Concept

Four-Band Resistor Color Code Decoding

Estimated Time:40s

Question 205Question →

Complete the statement regarding fixed resistor specifications and heat dissipation.

Fill in the blanks below

A resistor's ability to safely dissipate electrical energy as heat is measured in , and among standard carbon-composition resistors, a physically larger package indicates a power rating.

Show answer & explanation

Answer

watts (or W) and higher (or greater / larger)

Resistors convert electrical energy into heat during circuit operation. The rate of heat dissipation is rated in watts (W). Because standard carbon-composition and film resistors do not use color bands for wattage, their power ratings (such as 1/8 W, 1/4 W, 1/2 W, 1 W, or 2 W) are identified by their physical dimensions: larger physical dimensions provide greater surface area to radiate heat, allowing for a higher power rating.

Step-by-Step Solution

1

Identify the standard electrical unit for power dissipation in resistive components.

Power is measured in watts (W).

Electrical power converted into heat by a resistor is calculated using Watt's Law (

P = I^2 R = V \times I

) and expressed in watts.

2

Determine the physical property that dictates the wattage rating of standard carbon resistors.

Physical surface area and volume determine heat dissipation, meaning larger size equals a higher power rating.

Resistor color bands only specify resistance value and tolerance, not power rating; physically larger resistors have more surface area to radiate heat without burning out.

Key Concept

Resistor Power Rating and Physical Dimensions

Estimated Time:45s

Question 206Question →

An electronics technician connects a circuit using only the two outer stationary terminals of a $10\text{ k}\Omega$ potentiometer, leaving the center wiper terminal unconnected. How will the resistance between the two connected terminals behave as the adjustment shaft is rotated?

It remains constant at

10\text{ k}\Omega

regardless of shaft rotation.

It varies smoothly from

0\ \Omega

to

10\text{ k}\Omega

as the shaft turns.

It acts as an open circuit with infinite resistance because the wiper is disconnected.

It remains fixed at

5\text{ k}\Omega

across the circuit.

Show answer & explanation

Answer: It remains constant at $10\text{ k}\Omega$ regardless of shaft rotation.

Answer

The resistance remains constant at

10\text{ k}\Omega

regardless of shaft rotation.

A standard potentiometer has a continuous resistive element with fixed end contacts. Connecting exclusively to the two outer terminals places the entire

10\text{ k}\Omega

track in series with the circuit. Because the movable wiper is not part of the active electrical path, rotating the control shaft has no effect on the total resistance between the outer terminals.

Step-by-Step Solution

1

Identify the internal construction of a standard three-terminal potentiometer.

A potentiometer consists of a continuous resistive track of fixed total resistance (

10\text{ k}\Omega

) connected between its two outer stationary terminals, along with an adjustable center wiper that slides along that track.

Understanding the physical arrangement determines which paths conduct current.

2

Analyze the circuit path when only the two outer terminals are connected.

Current flows through the entire continuous length of the resistive strip from one end to the other without passing through the wiper.

Since the center wiper terminal is unconnected, its mechanical movement along the track cannot alter the total length or resistance between the two fixed outer end points.

Key Concept

Potentiometer terminal anatomy and resistive track behavior

Estimated Time:40s

Question 207Question →

Match each type of resistive component to its primary electrical characteristic or circuit application.

Click a left item, then click its matching right item

Show answer & explanation

Answer

Metal Film Resistor matches with high precision and low electrical noise; Wirewound Resistor matches with high power dissipation and coiled alloy wire construction; Potentiometer matches with three terminals providing an adjustable voltage division; Rheostat matches with two active terminals in series regulating circuit current.

Metal film resistors are characterized by high precision and low electrical noise. Wirewound resistors are characterized by high power dissipation and coiled wire construction. Potentiometers use three terminals to divide voltage, and rheostats use two terminals to adjust current in series.

Step-by-Step Solution

1

Identify the construction and operational profile of fixed resistor types.

Metal film resistors provide low noise and tight precision, whereas wirewound resistors provide high power and heat handling.

Film technologies provide precision at low power, while wound alloy wires allow high wattage dissipation.

2

Distinguish between the terminal configurations of variable resistors.

Potentiometers use three terminals for voltage division, while rheostats use two active terminals for series current limiting.

A three-terminal potentiometer splits an applied voltage across its track, whereas a two-terminal rheostat directly alters total series resistance.

3

Map each component identifier to its exact functional description.

Pairs are established: Metal Film to precision/low noise, Wirewound to high power/ceramic core, Potentiometer to three-terminal voltage divider, and Rheostat to two-terminal current regulator.

Each definition uniquely aligns with the physical and electrical design of the respective component.

Key Concept

Distinguishing construction, terminal configuration, and functional roles of fixed and variable resistive components.

Estimated Time:45s

Question 208Question →

A standard four-band through-hole resistor installed in an audio preamplifier has a specified nominal resistance of $47\text{ k}\Omega$ . If the first two color bands on the component are Yellow and Violet, what color must the third band be to indicate the correct multiplier?

Red

Orange

Yellow

Brown

Show answer & explanation

Answer: Orange

Answer

Orange

Orange is the correct multiplier band because the significant digits from Yellow (4) and Violet (7) combine to form 47. Multiplying 47 by the Orange multiplier (

10^3

or

1,000

) produces

47,000\ \Omega

, which equals the specified

47\text{ k}\Omega

.

Step-by-Step Solution

1

Determine the digits represented by the first two color bands.

Yellow corresponds to 4 and Violet corresponds to 7, forming the two-digit significant value 47.

In standard four-band EIA color coding, the first two bands establish the significant digits of the resistance value.

2

Convert the required resistance from kilohms into ohms.

47\text{ k}\Omega = 47 \times 10^3\ \Omega = 47,000\ \Omega

.

The metric prefix 'kilo' represents a factor of

1,000

(

10^3

).

3

Calculate the multiplier and identify the corresponding band color.

47,000 / 47 = 1,000 = 10^3

, which corresponds to the color Orange.

The third band indicates the power-of-ten multiplier (number of trailing zeros), where Orange denotes

10^3

.

Key Concept

Standard four-band resistor color code decoding and multiplier determination

Estimated Time:40s

Question 209Question →

A four-band resistor has color bands in the following sequence: Orange, White, Red, and Silver. Based on this color code, what is the maximum acceptable resistance value for this component in ohms ( $\Omega$ )?

Show answer & explanation

Answer: 4290

Answer

The maximum acceptable resistance value for the resistor is

4290\ \Omega

.

The first band (Orange) equals 3, the second band (White) equals 9, and the third band (Red) represents a multiplier of 100 (

10^2

), giving a nominal resistance of

3900\ \Omega

. The fourth band (Silver) specifies a

\pm 10\%

tolerance. Ten percent of

3900\ \Omega

is

390\ \Omega

, so the maximum acceptable resistance value is

3900 + 390 = 4290\ \Omega

.

Step-by-Step Solution

1

Decode the first two significant digit color bands.

Orange = 3, White = 9, giving base digits 39.

Standard four-band resistors use the first two bands to establish the two most significant digits.

2

Apply the multiplier from the third color band.

Red =

10^2 = 100

, so

R_{\text{nominal}} = 39 \times 100 = 3900\ \Omega

.

The third band indicates the power of ten multiplier applied to the significant digits.

3

Calculate the upper limit of the resistance range using the tolerance band.

Silver =

\pm 10\%

. Maximum limit

= 3900 + (0.10 \times 3900) = 3900 + 390 = 4290\ \Omega

.

The fourth band specifies the allowable percentage deviation from nominal resistance, and the maximum limit requires adding the tolerance value.

Key Concept

Standard four-band resistor color code decoding and percentage tolerance range calculation.

Estimated Time:45s

Question 210Question →

Complete the technical description of variable resistive components: What specific terms correctly complete the statement regarding the movable contact and the voltage-dividing component?

Fill in the blanks below

In a variable resistor, the adjustable mechanical contact that slides along the resistive track is called the , and a three-terminal device configured to provide an adjustable output voltage is known as a .

Show answer & explanation

Answer

The mechanical sliding contact is the wiper, and the three-terminal variable resistor configured to adjust voltage is a potentiometer.

A variable resistor contains a movable contact known as a wiper (or slider) that sweeps across a resistive strip. When all three terminals are utilized—two connected across a voltage source and one to the wiper—the component functions as an adjustable voltage divider called a potentiometer.

Step-by-Step Solution

1

Identify the component's internal mechanical contact mechanism.

The adjustable element that physically traverses the resistive track is termed the wiper.

The wiper provides an electrical connection at any point along the resistive element to pick off a variable resistance value.

2

Identify the standard three-terminal variable resistor designed for voltage adjustment.

A three-terminal variable resistor acting as a voltage divider is a potentiometer.

When connected across a potential difference with the wiper serving as the variable output, it functions as an adjustable voltage divider.

Key Concept

Variable Resistor Construction and Potentiometer Operation

Estimated Time:45s

Question 211Question →

An avionics technician is inspecting a four-band carbon composition resistor on a circuit board with the color band sequence: Red, Violet, Gold, and Gold. What is the nominal resistance and tolerance rating of this resistor?

270\ \Omega \pm 5\%

2.7\ \Omega \pm 5\%

2.7\text{ k}\Omega \pm 5\%

0.27\ \Omega \pm 5\%

Show answer & explanation

Answer: $2.7\ \Omega \pm 5\%$

Answer

The nominal resistance is

2.7\ \Omega

with a tolerance of

\pm 5\%

.

In standard four-band resistor color coding, Red represents 2, Violet represents 7, a Gold third band represents a multiplier of

0.1

, and a Gold fourth band represents

\pm 5\%

tolerance. Calculating

27 \times 0.1

gives

2.7\ \Omega \pm 5\%

.

Step-by-Step Solution

1

Decode the first two color bands into the significant digits.

The first band (Red) represents the digit

2

, and the second band (Violet) represents the digit

7

, forming the base number

27

.

Standard four-band EIA color codes use the first two bands for the primary significant figures.

2

Apply the multiplier value indicated by the third color band.

The third band is Gold, which indicates a multiplier factor of

10^{-1}

(

0.1

). Multiplying gives

27 \times 0.1 = 2.7\ \Omega

.

When Gold appears in the multiplier band position, it denotes a decimal factor of

0.1

for low-resistance values.

3

Determine the tolerance percentage from the fourth color band.

The fourth band (Gold) designates a

\pm 5\%

manufacturing tolerance.

The fourth band identifies the allowable deviation from the nominal resistance value.

Key Concept

Four-Band Resistor Color Code with Fractional Multipliers

Estimated Time:40s

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