# Resistance and Power MCQ Questions & Answers

Resistance and Power MCQs : This section focuses on the "Resistance and Power". These Multiple Choice Questions (MCQs) should be practiced to improve the Resistance and Power skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.

Question 1

How is power dissipated in a resistor?

A. by resistance
B. by voltage
C. by current
D. by heat

Question 2

Which formula shows a direct proportionality between power and voltage?

A. V = IR
B. P = VI
C. P = IR
D. I = V/R

Question 3

Power is defined as:

A. the rate at which energy is used
B. watts
C. energy
D. the rate at which energy is generated

Question 4

What are the two major categories for resistors?

A. low and high ohmic value
B. commercial and industrial
C. low and high power value
D. fixed and variable

Question 5

How much energy is stored if 6.24 x 1018 electrons are stored in 4 volts?

A. 4 joules
B. 1.56 x 1018 electrons
C. 1.56 coulombs
D. 2.496 x 1019 electrons

Question 6

Resistor tolerance is either printed on the component, or is provided by:

A. keyed containers
B. size
C. color code

Question 7

How many amps are used by a 100 watt, 120 volt light bulb?

A. 1.2 amps
B. 12000 amps
C. 830 mA
D. 12 amps

Question 8

A wire with a smaller cross-sectional area will produce:

A. less heat
B. more conductance
C. less resistance
D. more heat

Question 9

One ampere of current flowing through one ohm of resistance is equal to:

A. 1 horsepower
B. 1 Btu
C. 1 watt
D. 1 joule

Question 10

One problem with mechanically variable resistors is noticeable in audio circuits as:

A. scratchy noise
B. lack of bass response
C. variable volume
D. too much treble response

Question 11

How many joules of energy will a 10 W lamp dissipate in one minute?

A. 10 joules
B. 60 joules
C. 600 joules
D. 3600 joules

Question 12

A good fuse will have:

A. zero ohms resistance
B. a medium resistance
C. a high resistance
D. an infinite resistance

Question 13

If a metallic conductor has a positive temperature coefficient of resistance, then:

A. as temperature increases, resistance decreases
B. as current increases, resistance decreases
C. as voltage increases, current increases
D. as temperature increases, resistance increases

Question 14

The unit designator for resistance value is the:

A. ampere
B. ohm
C. volt
D. watt

Question 15

With a complex circuit, a supply source senses:

A. open circuit components
B. when voltages need to be increased
C. only a single resistive connection
D. when complex currents are needed

Question 16

Electrical equipment is protected against excessive current by a(n):

B. insulated glass container
C. metal ended coil
D. circuit opener

Question 17

What is the ratio of 13 to 47 expressed in percent?

A. 2.76%
B. 27.70%
C. 3.60%
D. 36.10%

Question 18

How do fixed resistors usually fail?

A. slowly over time
B. by increasing their value
C. by becoming an open circuit
D. by increasing their value and becoming an open circuit

Question 19

With 1 mA of current, what wattage rating should a 470 ohm resistor have?

A. 1/4 watt
B. 1/2 watt
C. 1 watt
D. 2 watts

Question 20

Power is measured in units of:

A. joules x charge
B. joules/work
C. joules x voltage
D. joules/time

Question 21

Good insulators:

A. have few electrons in their outer shells
B. have a large dielectric strength
C. have a small breakdown voltage
D. have many electrons in the nucleus

Question 22

What is the most commonly used conductor in electronics?

A. aluminum
B. copper
C. gold
D. silver

Question 23

If a variable resistor's resistance varies in a nonuniform manner as the shaft is moved, it is considered to be:

A. linear
B. defective
C. not wirewound
D. tapered

Question 24

What happens to current and resistance if the voltage doubles?

A. Current doubles and resistance doubles.
B. Current doubles and resistance is halved.
C. Current remains the same and resistance doubles.
D. Current doubles and resistance remains the same.

Question 25

How many connections does a rheostat have?

A. 1
B. 2
C. 3
D. 4

Question 26

A. vary
B. remain constant
C. increase
D. decrease

Question 27

What type of resistors have a tolerance rating of 5% or greater?

A. precision
B. SIP
C. general-purpose
D. wirewound

Question 28

What property does an incandescent lamp possess?

A. cold resistance
B. hot resistance
C. ballast resistance
D. both cold and hot resistance

Question 29

Resistors are identified as to wattage by:

A. size
B. color code
C. types of materials
D. internal construction

Question 30

With Ohm's law:

A. current is inversely proportional to resistance
B. resistance is directly proportional to voltage
C. voltage is indirectly proportional to power
D. current is directly proportional to resistance

Question 31

Ohm's law is not:

A. V = IR
B. I = V/R
C. R = IV
D. R = V/I

Question 32

Which type of test equipment is used to measure resistors?

A. ohmmeter
B. ammeter
C. voltmeter
D. watt meter

Question 33

A 22-gauge wire will have a diameter in mils of:

A. 10.03
B. 22.35
C. 45.26
D. 71.96

Question 34

The resistivity of copper is:

A. 9.9
B. 10.7
C. 16.7
D. 17

Question 35

With Ohm's law, no change in resistance means that current and voltage will be:

A. directly proportional
B. unable to produce energy
C. the same
D. inversely proportional

Question 36

What resistor type is found in SIPs and DIPs?

A. metal film
B. wirewound
C. metal oxide
D. thick film

Question 37

One advantage of a carbon film resistor over a carbon composition resistor is:

A. less circuit noise
B. smaller size
C. higher wattage
D. poor tolerance

Question 38

What are the parts of a rheostat?

A. wiper and resistor track
B. solenoid and armature
C. contact and wire wound
D. center tape and wiper

Question 39

The six basic forms of energy are:

A. light, sun, magnetic, chemical, electrical, and mechanical
B. electrical, mechanical, light, heat, magnetic, and chemical
C. electrical, mechanical, sun, heat, chemical, and light
D. potential, sun, light, chemical, electrical, and mechanical

Question 40

If resistance decreases, then current will:

A. decrease
B. increase
C. remain the same
D. double

Question 41

Resistance is:

A. the opposition to current flow accompanied by the dissipation of heat
B. symbolized by R, measured in ohms, and directly proportional to conductance
C. directly proportional to current and voltage
D. represented by the flow of fluid in the fluid circuit

Question 42

A color code of orange, orange, orange is for what ohmic value?

A. 22 kilohms
B. 3300 ohms
C. 44000 ohms
D. 33 kilohms

Question 43

After a lamp is turned on, its filament resistance will change to become:

A. less resistive
B. cooler
C. brighter
D. more resistive

Question 44

A potentiometer has how many leads?

A. 1
B. 2
C. 3
D. 4

Question 45

Components designed to oppose the flow of current are called:

A. insulators
B. conductors
C. resistors
D. heat exchangers

Question 46

If a calculator display was "0.00263," what would this answer be in percent?

A. 0.03%
B. 0.26%
C. 2.63%
D. 26.30%

Question 47

The word work means that:

A. energy has been transferred
B. it is inversely related to energy
C. no energy has been transferred
D. work and energy are not related

Question 48

Which is the most important step utilized when measuring resistors?

A. use the highest possible scale
C. zero the meter before using
D. remove power from the circuit

Question 49

Wirewound resistors are usually used in circuits that have:

A. high current
B. negative temperature coefficients
C. low power
D. high voltage

Question 50

With Ohm's law, if voltage increases and resistance stays the same:

A. current remains the same
B. power decreases
C. current increases
D. resistance decreases

Question 51

How many connections does a potentiometer have?

A. 1
B. 2
C. 3
D. 4

Question 52

How many basic types of resistors exist?

A. 1
B. 2
C. 3
D. 4

Question 53

Resistance in a circuit is:

A. opposition to current
B. opposition to voltage
C. the same as current
D. the same as voltage