MCQ on Current Electricity with Answers Pdf
MCQ Questions on Electricity with Answers :
We are providing here the important MCQ on Current Electricity. Students can practice these questions and answers to revise the key concepts. Students should do a lot of practice to score well on these questions. Get MCQ Questions on Current Electricity with Answers PDF Free Download of all subjects is prepared here according to the latest syllabus and curriculum. Students can practice Electricity Multiple Choice Questions with Answers to score good marks in the examination.
MCQ Questions for Class 12 Science Electricity with Answers
1. The unit of potential difference is________
A) Volt
B) Ohm
C) Ampere
D) Faraday
Answer: A
2. A fuse wire is inserted in which wire?
A) Live wire
B) In the neutral wire
C) In the earth wire
D) May be connected in any line
Answer: A
3. Unit of electric power may also be expressed as___________
A) volt-ampere
B) kilowatt-hour
C) watt’s second
D) joule’s second
Answer: B
4. The rate of flow of an electric charge is known as______________
A) Electric potential
B) Electric conductance
C) Electric current
D) None of these
Answer: C
5. To get 2 Ω resistance using only 6 Ω resistors, the number of them required is____________
A) 2
B) 3
C) 4
D) 6
Answer: B
6. Two devices are connected between two points say A and B in parallel. The physical quantity that will remain the same between the two points is________
A) current
B) voltage
C) resistance
D) None of these
Answer: B
7. A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of_________
A) more length
B) less radius
C) less length
D) more radius
Answer: D
8. What is the relationship between resistance and current?
A) They are directly related to each other.
B) They are inversely related to each other.
C) The resistance has a greater magnitude than the current.
D) The current has a greater magnitude than the resistance
Answer: B
9. Which of the given is the SI Unit of Electric Current?
A) Ohm
B) Ampere
C) Volt
D) Faraday
Answer: B
10. The relation between potential difference (V) and current (I) is___________
A) V α I2
B) V α 1/I
C) V2 α I
D) V α I
Answer: D
11. During the verification of Ohm’s law:
A) Ammeter and voltmeter should be connected in series
B) Ammeter should be connected in series and the voltmeter in parallel
C) ammeter should be connected in parallel and the voltmeter in series
D) Ammeter and voltmeter should be connected in parallel
Answer: B
12. Which of the following laboratory apparatus is not used during the verification of Ohm’s law:
A) Voltmeter
B) Ammeter
C) Galvanometer
D) Rheostat
Answer: C
13. The resistance of a conductor is directly proportional to_________________
A) Its area of cross-section
B) density
C) melting point
D) length
Answer: A
14.The purpose of a rheostat is___________
A) Increase the magnitude of current only
B) Decrease the magnitude of the currently only
C) Increase or decrease the magnitude of current
D) None of these
Answer: C
15. The resistance of a conductor is inversely proportional to its:
A) area of cross-section
B) length
C) specific resistance
D) density
Answer: A
16. Point to be kept in mind for verification of Ohm’s Law is______________
A) Ammeter and voltmeter should be connected in series
B) Ammeter should be connected in series and the voltmeter in parallel
C) Ammeter should be connected in parallel and the voltmeter in series
D) Ammeter and voltmeter should be connected in parallel
Answer: B
17. The north pole of Earth’s magnet is in the____________
A) Geographical South
B) Geographical East
C) Geographical West
D) Geographical North
Answer: A
18. An electric motor is a device which transforms______________
A) Mechanical energy into electrical energy
B) Electrical energy into mechanical energy
C) Kinetic energy into potential energy
D) Electrical energy into Potential energy
Answer: B
19. The frequency of electricity produced by DC generator is equal to_______________
A) 0 Hz
B) 50 Hz
C) 100 Hz
D) 200 Hz
Answer: A
20. How much more heat is produced, if the current is doubled?
A) twice the original amount
B) thrice the original amount
C) four times the original amount
D) five times the original amount
Answer: C
22. Which of the following represents voltage?
A) Work done / Current × Time
B) Work done × Charge
C) Work done × Time / Current
D) Work done × Charge × Time
Answer: A
23. The force exerted on a current-carrying wire placed in a magnetic field is zero when the angle between the wire and the direction of the magnetic field is________________
A) 45o
B) 60o
C) 90o
D) 180o
Answer: D
24. How can the electric charge be established?
A) Electrons can be removed from atoms and accumulated to produce a negative charge.
B) Atoms from which electrons have been removed produce a positive electric charge.
C) Both A and B.
D) Neither A nor B.
Answer: C
25. Two appliances of rating 200-watt-250 volts and 100-watt-250 volts are joined in series to a 250 volts supply. Total power consumed in the circuit is____________
A) 46 watt
B) 67 watts
C) 10 watt
D) 30 watt
Answer: B
26. A cooler of 1500 W, 200 volts, and a fan of 500 W, 200 volts are to be used from a household supply. The rating of fuse to be used is__________
A) 2.5 A
B) 5.0 A
C) 7.5 A
D) 10 A
Answer: D
27. Voltage is a form of________________
A) Kinetic energy
B) Potential energy
C) both Potential and Kinetic energy
D) None of the above
Answer: B
28. The curve representing Ohms law is a____________
A) Linear
B) cosine function
C) Parabola
D) Hyperbola
Answer: A
29. To produce an electric current what is the requirement?
A) A voltage source
B) A source of energy that moves charges
C) An electric field moving through a conductor
D) All
Answer: D
30. A galvanometer can be converted into a voltmeter by connecting___________
A) high resistance in series
B) low resistance in series
C) low resistance in parallel
D) high resistance in parallel
Answer: A
31. To measure the p.d. between two ends of a resistor in a circuit, the resistance of the voltmeter must be very large compared to_______
A) Other resistances in the circuit
B) the combined resistance of all the resistors in the circuit
C) the largest resistance in the circuit
D) the resistance of the resistor across which the meter is connected.
Answer: D
32. The current which is assumed to be flowing in a circuit from positive terminal to negative, is called______________
A) direct current
B) pulsating current
C) conventional current
D) alternating current
Answer: C
33. When no current is passed through a conductor__________
A) the free electrons do not move
B) the average speed of a free electron over a large period is not zero
C) the average velocity of a free electron over a large period is zero
D) the average of the velocities of all the free electrons at an instant is non zero
Answer: D
34. Drift velocity of electrons is due to_____________
A) motion of conduction electrons due to random collisions.
B) motion of conduction electrons due to electric field E
C) repulsion to the conduction electrons due to the inner electrons of ions.
D) collision of conduction electrons with each other.
Answer: B
35. What is the amount of current flowing through an electric press, if the amount of charge passing through a conductor in 10 minutes is 300 C?
A) 30 A
B) 0.3 A
C) 0.5 A
D) 5 A
Answer: C
36. A current-carrying rectangular coil placed in a uniform magnetic field. In which orientation will the coil rotate?
A) In any orientation
B) The magnetic field is parallel to the plane of the coil
C) The magnetic field is at 450 with the plane of the coil
D) The magnetic field is perpendicular to the plane
Answer: D
37. In the absence of an electric field, the mean velocity of free electrons in a conductor at absolute temperature (T) is______________
A) zero
B) independent of T
C) proportional to T
D) proportional to T2
Answer: A
Safe Electricity MCQ:
1) Regarding the following practices in the home circuit, the one that does not conform to the common sense of safe electricity use is______
A. If someone gets an electric shock, cut off the power first.
B. When overhauling circuit faults, try to work under power-on conditions.
C. For electrical appliances with metal shells, the metal shell must be grounded.
D. To ensure circuit safety, try not to use multiple high-power electrical appliances at the same time.
Answer: B
2) Which of the following practices does not meet the requirements for safe electricity use is______
A. Use copper wire instead of a fuse
B. When using the refrigerator, the power plug is inserted into the three-hole socket
C. In the event of an electric shock accident, immediately cut off the power supply
D. When using the test pen, the finger should not touch the tip of the pen
Answer: A
3) Which of the following statements conforms to the principle of safe electricity use is_______
A. There is one hole in the three-hole socket for connecting the ground wire
B. The switch is installed between the lamp and neutral
C. Simultaneous use of multiple high-power appliances in home circuits
D. The tripping of the air switch in the home circuit must be caused by a short circuit
Answer: A
4) The fuse in the household circuit has blown, the reason may be_______
A. short circuit
B. Someone was electrocuted
C. The filament of the light bulb is broken
D. There is an open circuit in the neutral line
Answer: A
5) Regarding household circuits and safe electricity use, which of the following statements is correct______
A. Fuse blown in the home circuit is caused by a short circuit
B. The light used for lighting and the switch that controls it only need to be connected in series
C. After the fuse is blown, copper wire can be used instead of the fuse to connect to the circuit
D. When a household appliance or electrical wire is found to be on fire, the power must be cut off before putting out the fire
Answer: D
6) With the improvement of people’s living standards, the types and numbers of household electrical appliances are increasing, which brings convenience to our lives and also brings security risks. Which of the following is correct___
A. The switch should be connected between the lamp and neutral
B. The metal shell of the electrical appliance does not need a ground wire
C. In the existing lighting circuit, when adding high-power electrical appliances, you only need to replace the fuse with a thick enough
D. When the circuit is cut off by the fuse device, the cause of the accident should be found first, and then the power supply should be restored after elimination.
Answer: D
7) Which of the following statements about household circuits and the safe use of electricity is correct______
A. The connection of the switch in the picture is wrong
B. The electrical appliances in the home circuit should be connected in parallel
C. When using the test pen, your fingers should not touch the metal body of the pen tail
D. The blown fuse may be caused by the total power of the electrical appliance being too large
Answer: D
8) Regarding the safe use of electricity, which of the following statements is incorrect________
A. When using electric kettles and rice cookers, the metal casing should be grounded
B. Usually, when replacing the light bulb, the switch of the branch circuit where the light bulb is located must be disconnected first.
C. Do not touch or wipe electrical appliances such as lamps and lanterns in working condition with wet hands or with a damp cloth to prevent electric shock
D. When using the electroscope to identify the phase (fire) line, the metal body at the front end of the pen should be connected to the phase (fire) line, and the hand should not touch the metal body at the end of the pen.
Answer: D
9) It is necessary to master some common sense of safe electricity use in life. The correct one of the following practices is______
A. Turn off the power before replacing the bulb
B. When an electrical appliance catches fire, first put out the fire with water, and then cut off the power
C. Dry wet clothes directly on power lines
D. When someone is found to be electrocuted, pull them away with their hands
Answer: A
10. It is necessary to master some common sense of safe electricity use in life. The correct one of the following practices is________
A. Turn off the power before replacing the bulb
B. When an electrical appliance catches fire, first put out the fire with water, and then cut off the power
C. Dry wet clothes directly on power lines
D. When someone is found to be electrocuted, pull them away with their hands
Answer: A
1) Any electrical device should not be overloaded or used with faults.
Answer: True
2) When using mobile electrical equipment and hand-held power tools, the grounding wire must be installed first. Qualified insulating equipment and safety protection equipment should be used.
Answer: True
3) Clothes should not be hung on the overhead line, but other non-flammable items may be placed or hung.
Answer: False
4) When inserting and unplugging the plug, the human body shall not touch the conductive electrode, and the power cord can be inserted and unplugged by pulling force.
Answer: False
5) When the insulation or casing of the electrical device is damaged, which may cause the human body to touch the live part, it can continue to be used under the condition of avoiding direct contact with the live part as much as possible.
Answer: False
6) In the event of a personal electric shock accident, to save the electric shock person, you can cut off the power supply of the relevant equipment without permission, but you must report to the superior immediately after the event.
Answer: True
7) When someone gets an electric shock, first aid must be carried out very accurately, calmly, and quickly, and the first job is to carry out artificial respiration.
Answer: False
8) Electric test pens, insulated gloves, insulated shoes, insulated pliers, and screwdrivers are the basic safety tools for electricians.
Answer: True
9) When a fire is found due to electrical failure or leakage, immediately put out the fire with water or a foam fire extinguisher.
Answer: False
10) Any hand-held power tool must be equipped with a leakage protector when using it, and the operator must wear insulating gloves and insulating shoes.
Answer: True
11) Under normal circumstances, 36V is a safe voltage, so 12V is absolutely safe.
Answer: False
12) Because the neutral wire is safer than the live wire, the switches are mostly installed on the neutral wire.
Answer: False
13) The key points of first aid for electric shock are quick and effective rescue.
Answer: True
14) For more serious electrical fires, put out the fire first, and then cut off the power.
Answer: False
15) In the three-phase line, the yellow, green, and red wires are used as the live wire, and the light blue wire is used as the neutral wire.
Answer: True