Physics: Electric Current MCQ Quiz 2

Question 1. Full form of C.F.L. is _________.

(A) Condensed Fluorescent Lamp

(B) Chemical Fluorescent Lamp

(C) Centrally Fixed Lamp

(D) Compact Fluorescent Lamp

Question 2. What gases are filled in fluorescent tube?

(A) Mercury and neon

(B) Mercury

(C) Sodium

(D) Neon

Question 3. In comparison to an electric bulb, a fluorescent tube is preferred because _________.

(A) It has greater external outer surface to radiate/emit the light

(B) In the tube, electric energy almost converted into light energy

(C) There is no effect of voltage fluctuation on it

(D) None of the above

Question 4. How does the white light produce in the tube?

(A) To oscillate molecule

(B) To accelerate the atoms

(C) To heat up the filament

(D) To heat up the copper wire

Question 5. Which is the gas inside an electric bulb?

(A) Argon

(B) Nitrogen

(C) Carbon dioxide

(D) Both (A) and (B)

Question 6. Fluorescent tubes are fitted with a choke. The choke coil ________.

(A) Chokes low frequency current

(B) Reduces current in the circuit

(C) Steps down the line voltage

(D) Steps up the line voltage

Question 7. A mobile phone charger is ______.

(A) A step down transformer

(B) A step up transformer

(C) A UPS

(D) An inverter

Question 8. If potential difference and current flowing through a wire is increased twice each, then electric power.

(A) Will decrease half

(B) Will increase two times

(C) Will increase four times

(D) Will remain unaffected

Question 9. Two wires have their lengths, diameters and resistivities all in the ratio of 1 : 2. If the resistance of the thinner wire is 10 ohm, the resistance of the thicker wire is ________.

(A) 40 ohm

(B) 20 ohm

(C) 10 ohm

(D) 5 ohm

Question 10. Small drops of the same size are charged to V volts each. If n such drops coalesce to form a single large drop, its potential will be.

(A) n –1V

(B) nV

(C)  n 1/3V

(D) n 2/3V

Question 11. Transformer is used for_________.

(A) To step up or step down AC voltages

(B) To step up DC voltages

(C) Converting DC into AC

(D) Converting AC into DC

Question 12. Alternate current is not preferable_______.

(A) To heat up electric toaster

(B) To transmit electric power

(C) To run/start an electric motor

(D) To charge storage battery

Question 13. The device used for converting alternating current to direct current is called ______.

(A) Transmitter

(B) Transformer

(C) Rectifier

(D) Inverter

Question 14. Alternating current is converted to direct current ________.

(A) By Rectifier

(B) By Transformer

(C) By Motor

(D) By Dynamo

Question 15. Which of the following option represents the consumption of power in ascending order?

(A) Electronic press, electronic kettle, fan, television

(B) Fan, television, electronic press, electronic kettle

(C) Television, fan, electronic kettle, electronic press

(D) Television, fan, electronic press, electronic kettle

Question 16. The Earth’s magnetic field is due to______.

(A)  Currents circulating inside the core

(B) Moving charges in space outside

(C) Presence of a huge magnet at its centre

(D) None of the above

Question 17.Nickel-Cadmium (Ni-Cd) battery is used in________.

(A) Calculator

(B) Transistors

(C) Cordless electronic appliances

(D) All of the above

Question 18. Electricity consumption bill is based on the measurement of:

1. Watt
2. Voltage
3. Ohm
4. Ampere

Select your answer of the following codes.

(A) 1 and 4

(B) 2 and 3

(C) 1 and 2

(D) Only 1

Question 19. Consider the following statements regarding a motor car battery.

1. The voltage is usually 12V.
2. Electrolyte used is hydrochloric acid.
3. Electrodes are lead and copper.
4. Capacity is expressed in ampere-hour.

Which of the above statements are correct?

(A) 1 and 4

(B) 3 and 4

(C) 2 and 3

(D) 1 and 2

Question 20. Consider the following statements. An ordinary light bulb has a rather short life because the

1. Filament wire is not uniform.
2. Bulb cannot be evacuated completely.
3. Wires supporting the filament melt at high temperatures.

Which of the above statements are correct? 

(A) 1, 2 and 3

(B) 1 and 3

(C) 2 and 3

(D) 1 and 3

Question 21. Consider the following statements.

• Assertion (A): Lightning conductors prevent buildings from damages in the event of lightning strike.
• Reason (R): The electric charge conduct to ground through the wire, instead of passing through the structure.

Select the correct answer using the codes given below.

(A) (A) is false, but (R) is true

(B) (A) is true, but (R) is false

(C) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

(D) Both (A) and (R) are true and (R) is the correct explanation of (A)

Question 22.

• Assertion (A): The temperature of a metal wire rises when an electric current is passed through it.
• Reason (R): Collision of metal atoms with each other releases heat energy.

(A) (A) is false, but (R) is true

(B) (A) is true, but (R) is false

(C) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

(D) Both (A) and (R) are true and (R) is the correct explanation of (A)

Question 23.

• Assertion (A): Light Emitting Diode (LED) lamps offer longer service life as compared to Compact Fluorescent Lamps (CFL).
• Reason (R): Light Emitting Diodes (LED) lamps are more energy efficient as compared to Compact Fluorescent Lamps (CFL).

Select the correct answer using the codes given below.

Code 

(A) (A) is false, but (R) is true

(B) (A) is true, but (R) is false

(C) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

(D) Both (A) and (R) are true and (R) is the correct explanation of (A)

Question 24. What is the difference between a CFL and an LED lamp?

1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semiconductor material.
2. The average life span of a CFL is much longer than of an LED lamp.
3. A CFL is less energy efficient as compared to an LED lamp.

Which of the statements given above is/are correct?

(A) 1, 2 and 3

(B) 1 and 3

(C) 2 and 3

(D) Only 1

Question 25. Given below are two statements, one labelled as Assertion (A) and the other labelled as Reason (R).

• Assertion (A): Transformer is useful for stepping up or stepping down voltages.
• Reason (R): Transformer is a device used in D.C. circuits.

In the context of the above two statements, which one of the following is correct? 

(A) (A) is false, but (R) is true

(B) (A) is true, but (R) is false

(C) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

(D) Both (A) and (R) are true and (R) is the correct explanation of (A)

Question 26. Some pairs of devices and associated energy changes are given below.

1. Electric generator – Mechanical to electrical
2. Electric motor – Electrical to mechanical
3. Diesel engine – Light to electrical
4. Solar cell – Chemical to mechanical

Which of the above pair/s is/are correctly matched?

(A) 3 and 4

(B) 2 and 4

(C) 1 and 3

(D) 1 and 2

Question 27.

• Assertion (A): In India, electricity distribution companies calculate the consumption of electricity in kWh.
• Reason (R): Electrical system in India works at a frequency of 60 Hz.

(A)  (A) is false, but (R) is true

(B)  (A) is true, but (R) is false

(C) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

(D) Both (A) and (R) are true and (R) is the correct explanation of (A)