Explore topic-wise MCQs in Electronics.

This section includes 1177 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.

101.

Rheostat is added to increase field excitation.

A. in the circuit of the alternator
B. in the supply circuit
C. in the field of shunt generator
D. in the circuit of the armature
Answer» B. in the supply circuit
102.

What is the material of transformer core?

A. silicon-steel
B. silicon
C. cobalt
D. aluminum
Answer» B. silicon
103.

Transformers that convert low voltage to high voltage are called?

A. step up
B. Step down
C. both A and B
D. none of these
Answer» B. Step down
104.

Substances split into their ions is called?

A. Replacement
B. polarization
C. Ionization
D. electrolysis
Answer» E.
105.

Using Damper Winding in Alternator?

A. the machine becomes more balanced
B. The whirlpool current decreases
C. Hating ends
D. armature reaction decreases
Answer» D. armature reaction decreases
106.

Which lamp method should be adopted if the synchronizing three phase alternator is to be done?

A. One Dark Two Bright Lamp Method
B. Bright Lamp Method
C. dark lamp method
D. suitable all
Answer» E.
107.

Driven e in rotating machines

A. Working flux lags from to 90॰
B. Working flux to 90 leads
C. Working flux occurs in the art of
D. Working flux lags from to 180॰
Answer» B. Working flux to 90 leads
108.

Which of the following cannot be a permanent indicator of a substance?

A. stainless steel
B. soft iron
C. hardened steel
D. Nickel to Volt Alloy
Answer» C. hardened steel
109.

What is the unit of ampere-hour?

A. Power
B. amount of electricity
C. strength of current
D. energy
Answer» C. strength of current
110.

Is there a potential difference?

A. resistance between two points
B. difference of electric potential between two points in an electric circuit
C. current difference between two points
D. none in suitable
Answer» D. none in suitable
111.

e of a magnetic circuit

A. electromotive force
B. of the stream
C. of force
D. of volts
Answer» B. of the stream
112.

Are wires used for staywire and earthing?

A. of brass wire
B. of copper
C. of GI wire
D. of aluminum wire
Answer» C. of GI wire
113.

Kitkat fuse over headline insulators are made from?

A. asbestos
B. micanite
C. glass
D. parsley
Answer» E.
114.

How to check the charging status of the battery?

A. by micrometer
B. from phase tester
C. With High Rate Cell Discharge Tester
D. by hygrometer
Answer» D. by hygrometer
115.

After a lead acid battery is fully charged, the active substances on the positive and negative plates are?

A. Lead Sulphate and Lead Peroxide
B. lead sulfate and lead
C. pure lead and lead oxide
D. lead peroxide and pure lead
Answer» E.
116.

If both ends of a charged capacitor are shorted?

A. voltage will be generated
B. There will be sparking
C. Nothing will happen
D. torque will be
Answer» C. Nothing will happen
117.

Studs are made in a three point starter?

A. of tungsten
B. of copper
C. of hard brass
D. of aluminum
Answer» D. of aluminum
118.

What is the amount of heat required to raise the temperature of one gram of water by 1॰C?

A. one calorie
B. one joule
C. 5 calories
D. suitable all
Answer» B. one joule
119.

Blue glow in Mercury Arc rectifier?

A. due to ionization
B. electron current is caused by
C. caused by high temperature
D. suitable all
Answer» B. electron current is caused by
120.

In table fan there is uneven air gap between stator and rotor, what is the disadvantage in this?

A. motor burn out
B. magnetizing hanning
C. low speed
D. speed up and down
Answer» C. low speed
121.

Coiled filament is used?

A. in low power lamp
B. in gas filled lamp
C. in high power lamps
D. in white light bulbs
Answer» C. in high power lamps
122.

A device that can increase or decrease voltage and current (without changing power) without changing the frequency is called?

A. DC. Motor
B. generator
C. AC Motor
D. Transformer
Answer» E.
123.

Lamps are used in light houses, search lights, cinema projectors?

A. tungsten filament
B. HPMV Lamp
C. arc lamp
D. neon lamp
Answer» D. neon lamp
124.

What are NPN and PNP?

A. Transistor
B. valve
C. Resistance
D. Capacitors
Answer» B. valve
125.

The rotor winding of a synchronous motor is excited by

A. dc supply from exciter
B. ac supply
C. induction of stator current
D. cruising area
Answer» B. ac supply
126.

Three delta connected identical coils draw 400V, 5KW power and 90A line current from 3 supplies. What is the total KVA taken by the coils?

A. 1.0KVA
B. 2.5 KVA
C. 30KVA
D. 60KVA
Answer» C. 30KVA
127.

The resistance of the silver wire increases?

A. when the radius is doubled
B. on increasing length
C. on decreasing length
D. when the diameter is greater
Answer» C. on decreasing length
128.

Should the fuse always be connected?

A. in parallel with the neutral conductor
B. in the rank of apathetic driver
C. in parallel to the live wire
D. in series with live wire
Answer» E.
129.

This type of circuit breaker does not have any repairable parts.

A. air circuit breaker
B. oil circuit breaker
C. air blast circuit breaker
D. miniature circuit breaker
Answer» E.
130.

high voltage d

A. open tapered
B. semi-closed type
C. closed type
D. open doublet
Answer» E.
131.

The function of a protection relay is performed in a transformer.

A. Exploin Vent
B. temperature gauge
C. Bacchus relay
D. Earth point
Answer» D. Earth point
132.

A 230 V, dc series motor is connected to 230 V, ac, the motor?

A. run with low efficiency
B. won't work
C. speed will decrease
D. none of the suitable
Answer» B. won't work
133.

International ohm is defined as the resistance of?

A. unit length of metallic wire
B. Columns of mercury
C. copper cubes
D. cubes of carbon
Answer» C. copper cubes
134.

A plywood board is to be heated to 100॰. What would be the appropriate heating method for this?

A. resistive heating
B. arc heating
C. induction heating
D. none of the suitable
Answer» D. none of the suitable
135.

more capacity d

A. swinburne test
B. blocked rotor test
C. hopkinson test
D. ward leonard test
Answer» B. blocked rotor test
136.

At what distance is the wiring from the ceiling to the wall?

A. 1 meter
B. 1/2 meter
C. 45 cm.
D. m 2
Answer» D. m 2
137.

Frequency is controlled?

A. By turning off the alternator
B. at the speed of the primer
C. by Exciter
D. suitable all
Answer» E.
138.

Which of the following is the correct temperature to operate a tungsten filament lamp filled with gas?

A. 1200॰C
B. 1035॰C
C. 2300॰C
D. 1500॰C
Answer» D. 1500॰C
139.

Used in modern equipment?

A. तंगर दिष्टकारी
B. mercury arc rectifier
C. metallic rectifier
D. solid state rectifier
Answer» E.
140.

For what tasks is the heating method by radiation suitable

A. melting ferrous metals
B. Boiling of liquids in an electric kettle
C. annealing of metals
D. paint and varnish drying
Answer» E.
141.

A hole is made in the vent plug, in the cover of the battery?

A. To protect the battery and drain the gas
B. For beauty
C. to let out gas
D. suitable all
Answer» B. For beauty
142.

Where are fuel cells used?

A. in turbine operation
B. in nuclear reactor
C. Gemini space craft
D. none of the suitable
Answer» D. none of the suitable
143.

What is the diameter of a fluorescent tube?

A. 30MM to 70MM
B. 20MM to 40MM
C. 60MM to 100MM
D. 40MM to 60MM
Answer» C. 60MM to 100MM
144.

In the rotor of squirrel phase motor, the rod is placed between the laminated core?

A. Eureka's
B. nichrome key
C. of tungsten
D. of copper
Answer» E.
145.

What is required for automatic control of furnace temperature?

A. Heating Element of Variable Resistance
B. Thermostat
C. auto transformer
D. thermocouple
Answer» C. auto transformer
146.

What is the maximum voltage of LED?

A. 5V
B. 8V
C. 10V
D. 12V
Answer» C. 10V
147.

The impedance of the operation amplifier?

A. is high
B. is below
C. Zero
D. very low but not zero
Answer» E.
148.

What is the appropriate method to heat insulators and plastic materials?

A. by oil ignition method
B. resistance method
C. dielectric thermal method
D. by coal furnace
Answer» D. by coal furnace
149.

Which of the following substances will have the lowest temperature range?

A. eureka
B. nichrome
C. Canthal
D. Carbon
Answer» B. nichrome
150.

What if a single-phase, 230 volt, 48 inch ceiling fan is operated at 120 volts?

A. it will run at normal speed but get very hot
B. it will slow down
C. it won't work
D. it will run at normal speed
Answer» C. it won't work