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
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 2
What is the ratio of 13 to 47 expressed in percent?
A. 2.76%
B. 27.70%
C. 3.60%
D. 36.10%
Question 3
How many connections does a potentiometer have?
A. 1
B. 2
C. 3
D. 4
Question 4
A potentiometer has how many leads?
A. 1
B. 2
C. 3
D. 4
Question 5
How many basic types of resistors exist?
A. 1
B. 2
C. 3
D. 4
Question 6
How many connections does a rheostat have?
A. 1
B. 2
C. 3
D. 4
Question 7
The resistivity of copper is:
A. 9.9
B. 10.7
C. 16.7
D. 17
Question 8
A 22-gauge wire will have a diameter in mils of:
A. 10.03
B. 22.35
C. 45.26
D. 71.96
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
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 11
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 12
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 13
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 14
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 15
For P = V2/R, a decrease in resistance should produce:
A. a decrease in power
B. an increase in ohms
C. an increase in power
D. a decrease in current
Question 16
A good fuse will have:
A. zero ohms resistance
B. a medium resistance
C. a high resistance
D. an infinite resistance
Question 17
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 18
What property does an incandescent lamp possess?
A. cold resistance
B. hot resistance
C. ballast resistance
D. both cold and hot resistance
Question 19
How is power dissipated in a resistor?
A. by resistance
B. by voltage
C. by current
D. by heat
Question 20
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 21
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 22
Electrical equipment is protected against excessive current by a(n):
A. fusible wire link
B. insulated glass container
C. metal ended coil
D. circuit opener
Question 23
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 24
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 25
The load resistance increases. How will the load current change?
A. vary
B. remain constant
C. increase
D. decrease
Question 26
If resistance decreases, then current will:
A. decrease
B. increase
C. remain the same
D. double
Question 27
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 28
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 29
Components designed to oppose the flow of current are called:
A. insulators
B. conductors
C. resistors
D. heat exchangers
Question 30
Wirewound resistors are usually used in circuits that have:
A. high current
B. negative temperature coefficients
C. low power
D. high voltage
Question 31
Which formula shows a direct proportionality between power and voltage?
A. V = IR
B. P = VI
C. P = IR
D. I = V/R
Question 32
Resistors are identified as to wattage by:
A. size
B. color code
C. types of materials
D. internal construction
Question 33
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 34
Power is measured in units of:
A. joules x charge
B. joules/work
C. joules x voltage
D. joules/time
Question 35
A wire with a smaller cross-sectional area will produce:
A. less heat
B. more conductance
C. less resistance
D. more heat
Question 36
After a lamp is turned on, its filament resistance will change to become:
A. less resistive
B. cooler
C. brighter
D. more resistive
Question 37
Resistor tolerance is either printed on the component, or is provided by:
A. keyed containers
B. size
C. color code
D. ohmmeter reading
Question 38
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 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
Ohm's law is not:
A. V = IR
B. I = V/R
C. R = IV
D. R = V/I
Question 41
Which is the most important step utilized when measuring resistors?
A. use the highest possible scale
B. keep test leads short
C. zero the meter before using
D. remove power from the circuit
Question 42
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 43
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 44
What is the most commonly used conductor in electronics?
A. aluminum
B. copper
C. gold
D. silver
Question 45
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 46
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 47
Resistance in a circuit is:
A. opposition to current
B. opposition to voltage
C. the same as current
D. the same as voltage
Question 48
What resistor type is found in SIPs and DIPs?
A. metal film
B. wirewound
C. metal oxide
D. thick film
Question 49
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 50
The unit designator for resistance value is the:
A. ampere
B. ohm
C. volt
D. watt
Question 51
Which type of test equipment is used to measure resistors?
A. ohmmeter
B. ammeter
C. voltmeter
D. watt meter
Question 52
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 53
What type of resistors have a tolerance rating of 5% or greater?
A. precision
B. SIP
C. general-purpose
D. wirewound
Question 54
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