Electricity: MCQ Test (50 questions)

Question 1 of 50

When an ebonite rod is rubbed against the skin of a cat, the ebonite rod-

Abecomes negatively charged
BIt becomes positively charged.
Cremains indifferent
Dfirst negatively charged then positively charged

Question 2 of 50

In a three pin electrical plume the longest pin should be connected to-

Afrom the base end
BSanjeev from the beginning
Cfrom an indifferent head
Dfrom any end

Question 3 of 50

If a resistive wire is made longer, then its resistance-

Aincreases
Bdecreases
Cremains constant
DAll of these

Question 4 of 50

Kilowatt hour is the unit of what?

Apotential difference
Belectric power
Celectrical energy
Delectric potential

Question 5 of 50

Ampere is the unit of measurement of what?

Avoltage
Belectric current
Cresistance
DPower

Question 6 of 50

"In the process of electrolysis, the amount of substance liberated at an electrode is directly proportional to the total charge flowing through it. This law is-

AFaraday's first law of electrolysis
BFaraday's second law of electrolysis
CFaraday's third law of electrolysis
Dnone of these

Question 7 of 50

'Dry cell' is-

Aprimary cell
BSecondary Cell
Ctertiary cell
Dquartile cell

Question 8 of 50

The algebraic sum of the currents meeting at a point in a circuit is-

Ainfinite
BZero
Cbetween zero and infinity
Dnone of the above

Question 9 of 50

100 W electric bulb is used for 10 hours a day. How many units of energy will be used in 30 days?

A1
B10
C30
D300

Question 10 of 50

What is the resistance of an ideal voltmeter?

AZero
BLower
CUnlimited
DHigh

Question 11 of 50

Which of the following is the best conductor of electricity?

ACopper
BIron
Caluminum
DSilver

Question 12 of 50

A fuse wire is identified by which of these characteristics?

ALowest resistivity and high melting point
BHigh resistivity and high melting point
Chigh resistivity and low melting point
DLowest resistivity and lowest melting point

Question 13 of 50

When a bulb is broken, a loud noise is produced because-

AAir rapidly enters the vacuum inside the bulb
BThere is explosive gas inside the bulb.
CThe filament of the bulb reacts with air
DThe gas inside the bulb suddenly expands.

Question 14 of 50

A conductor has a resistance of 440 ohms. How much current will flow through it if it is connected to a 110 volt source?

A0.5A
B0.25A
C4A
D1.25A

Question 15 of 50

Earth is used in electrical equipment for-

Ato reduce expenses
BBecause the appliances operate on 3-phase
CFor safety
DAs a fuse

Question 16 of 50

The total charge of a charged conductor is its-

Aresides on the inside page
Blives on an external page
CSome are on the inner page and some are on the outer page.
DAll are true

Question 17 of 50

Which one of the following non-metals is not a poor conductor of electricity?

ASulphur
BSelenium
Cbromine
DPhosphorus

Question 18 of 50

Which of the following are used as electrolytes in a dry match (battery)?

AAmmonium chloride and zinc chloride
Bsodium chloride and calcium chloride
CMagnesium Chloride and Zinc Chloride
DAmmonium chloride and calcium chloride

Question 19 of 50

Which of the following is not a semiconductor?

AGermanium
BSilicon
CSelenium
DArsenic

Question 20 of 50

What is the source of electrical energy in an artificial satellite?

AThermopile
BSolar Cell
Csmall nuclear reactor
DDynamo

Question 21 of 50

How much is 1 volt equal to?

A1 joule
B1 joule/coulomb
C1 newton coulomb
D1 joule/newton

Question 22 of 50

If a 100 watt electric bulb burns for 10 hours, then the electricity cost at the rate of ₹5 per unit will be-

A₹ 5
B₹ 10
C₹ 25
D₹ 50

Question 23 of 50

The unit of resistance is-

AAmpere
BCoulomb
CHenry
DOm

Question 24 of 50

If the electrical resistance of a typical substance drops to zero, what is that substance called?

Asuperconductor
Bsemiconductor
CDriver
Danti-inflammatory

Question 25 of 50

The length of a wire is L meters, the wire is stretched to 21 meters; now the resistance of the wire will be-

Adouble the previous
Bfour times the previous
Ca quarter of the first
Dwill remain unchanged

Question 26 of 50

"The potential difference across the ends of a conductor is directly proportional to the current flowing through it." This law is-

ACoulomb's law
BFaraday's law
CJoule's law
DOhm's law

Question 27 of 50

The filament of an electric bulb is made of which element?

ACopper
BIron
Clead
Dtungsten

Question 28 of 50

Which instrument measures electrical resistance?

AAmmeter
Bpotentiometer
Cvoltameter
Dohm meter

Question 29 of 50

Those substances which do not have free electrons in normal state, but free electrons can be obtained under special conditions like high temperature or by adding impurities, are called-

Agood conductor material
Binsulator material
Cdielectric material
Dsemiconductor material

Question 30 of 50

What is the purpose of choke in fluorescent lamp?

Areducing the flow of current
Bincrease the flow of current
Creduce resistance
DMomentary voltage reduction

Question 31 of 50

The electrolyte in a typical dry cell is-

AZinc
Bsulfuric acid
Cammonium chloride
Dmanganese dioxide

Question 32 of 50

A fuse wire is used for

Atransmit high electric current without causing harm
Bbreak the electric circuit when excessive current flows
Cto protect a person from electric shock
Dnone of these

Question 33 of 50

You're traveling in a car. To stay safe if lightning is about to strike:

Aclose the car windows
Bopen the car windows
CGet out of the car and sit down
Dsit on top of the car

Question 34 of 50

Approximately how much of the energy consumed in a tube light is converted into light?

A30-40%
B40-50%
C50-60%
D60-70%

Question 35 of 50

The force between two stationary charges is directly proportional to the product of their quantities and inversely proportional to the square of the distance between them." This law is—

AOhm's law
BKirchhoff's law
CCoulomb's law
DFaraday's law

Question 36 of 50

A fuse is installed in the electrical supply mesh as a safety device. Which statement is correct regarding electrical fuses?

AIt is connected in parallel with the mains switch
BIt is mainly made of silver alloys.
CIts melting point is low
DIts resistance is very high.

Question 37 of 50

A metallic wire having a resistance of 200 Ω is cut lengthwise into two equal parts and then these parts are connected in parallel. What is the resistance of this parallel combination equal to?

A1Ω
B10Ω
C5 ohms
D15Ω

Question 38 of 50

The instrument used to detect the presence of electric current in a circuit is-

Arefractometer
Bgalvanometer
Cviscometer
Ddiffractometer

Question 39 of 50

A 100-watt electric lamp is used for 10 hours a day. How many units of energy does the lamp consume in a day?

A1 unit
B0.1 unit
C10 units
D100 units

Question 40 of 50

A current carrying conductor is related to-

Afrom the magnetic field
Bfrom the electric field
Cfrom the electromagnetic field
Dfrom the electrostatic field

Question 41 of 50

The device used to change the speed of an electric fan is-

Aamplifier
Bregulator
CSwitch
DRectifier

Question 42 of 50

Fluorescent tubes are preferred over electric bulbs because-

AIts illuminating surface is large
BIt is not affected by voltage fluctuations
CElectrical energy in the tube is almost completely converted into light energy
DIts light is not harmful to the eyes.

Question 43 of 50

The safety fuse wire used in domestic electrical appliances is made of the metal whose-

Aresistance is low
Bhave a lower melting point
Cthe specific density is low
Dconductivity is low

Question 44 of 50

Which of the following is marked on commonly used fluorescent tube lights?

A220 K
B273 K
C6500 K
D9000 K

Question 45 of 50

If the distance between two electric charges is halved, then the value of the electric force between them will become-

Ahalf
Bdouble
Cquadruple
Done fourth

Question 46 of 50

The electrical resistance of a conductor is independent of

Atemperature
Bpressure
Ccross-sectional area
Dlength

Question 47 of 50

The charging of objects occurs as a result of the transfer of-

Aelectron
BPositron
CProton
DNeutron

Question 48 of 50

A fuse wire is used in an electric circuit to

ATo reduce the cost of electrical energy transmission
BTo keep the voltage level constant
CTo prevent excess current from flowing through a circuit
DTo prevent the electrical wire from overheating

Question 49 of 50

The MCB which cuts off the power supply in case of a short circuit works by—

AOn the magnetic effect of current
Belectroplating effect of current
COn the chemical effects of current
DOn the heating effect of current

Question 50 of 50

Transformers are used in-

ATo convert AC to DC
BTo convert DC to AC
CTo oxidize DC voltage
DTo oxidize or reduce AC voltage