📘 Chapter 3 – Electricity: Circuits and their Components

🔹 Part 1: Introduction to Electricity (Q1–Q25)

Q1. Electricity is the flow of:

A) Atoms
B) Protons
C) Electrons
D) Neutrons

✅ Answer: C) Electrons

Explanation:

• (A) Atoms → Too large to flow.
• (B) Protons → Stationary inside nucleus.
• (C) Electrons → Move through conductors, producing electricity (Correct).
• (D) Neutrons → Neutral, do not flow.

Q2. A complete path for current to flow is called:

A) Magnet
B) Circuit
C) Switch
D) Battery

✅ Answer: B) Circuit

Explanation:

• (A) Magnet → Unrelated to electric flow.
• (B) Circuit → Complete conducting path for electricity (Correct).
• (C) Switch → Device to open/close a circuit.
• (D) Battery → Provides source, not the path.

Q3. Which device is used to open or close an electric circuit?

A) Cell
B) Wire
C) Switch
D) Bulb

✅ Answer: C) Switch

Explanation:

• Cell → Provides energy.
• Wire → Provides path.
• Switch → Opens or closes a circuit (Correct).
• Bulb → Glows when current flows.

Q4. In which case will a bulb glow?

A) If switch is off
B) If circuit is complete
C) If there is a break in circuit
D) If no battery is connected

✅ Answer: B) If circuit is complete

Q5. Electric current is measured in:

A) Watt
B) Ampere
C) Ohm
D) Volt

✅ Answer: B) Ampere

Explanation:

• Watt → Unit of power.
• Ampere → Unit of current (Correct).
• Ohm → Unit of resistance.
• Volt → Unit of potential difference.

Q6. Which instrument measures electric current?

A) Ammeter
B) Voltmeter
C) Galvanometer
D) Thermometer

✅ Answer: A) Ammeter

Q7. Which of these is the source of electricity?

A) Cell
B) Bulb
C) Switch
D) Wire

✅ Answer: A) Cell

Explanation:
Cell or battery supplies electrical energy.

Q8. Electricity produced from moving water is called:

A) Thermal electricity
B) Solar electricity
C) Hydro electricity
D) Nuclear electricity

✅ Answer: C) Hydro electricity

Q9. Which of the following is a good conductor of electricity?

A) Plastic
B) Wood
C) Copper
D) Rubber

✅ Answer: C) Copper

Q10. Which is a renewable source of electricity?

A) Coal
B) Petrol
C) Wind
D) Diesel

✅ Answer: C) Wind

Q11. Which is NOT required for a circuit?

A) Battery
B) Bulb
C) Wire
D) Magnet

✅ Answer: D) Magnet

Q12. Which energy is converted into electrical energy in a battery?

A) Chemical energy
B) Light energy
C) Sound energy
D) Heat energy

✅ Answer: A) Chemical energy

Q13. The direction of electric current is taken as flow of:

A) Negative charges
B) Positive charges
C) Neutrons
D) Protons only

✅ Answer: B) Positive charges

Explanation:
Conventionally current flows from + to – terminal (though electrons flow opposite).

Q14. Which of the following does not conduct electricity?

A) Iron nail
B) Plastic scale
C) Copper wire
D) Aluminium foil

✅ Answer: B) Plastic scale

Q15. Which of the following is a device that produces electricity?

A) Electric bulb
B) Electric cell
C) Switch
D) Wire

✅ Answer: B) Electric cell

Q16. A torch works on:

A) Solar cells
B) Electric cells
C) Generator
D) Motor

✅ Answer: B) Electric cells

Q17. Which statement is correct about current?

A) It flows only if circuit is complete
B) It flows even if switch is off
C) It flows without a source
D) It can flow through wood

✅ Answer: A) It flows only if circuit is complete

Q18. The SI unit of voltage is:

A) Joule
B) Volt
C) Watt
D) Ampere

✅ Answer: B) Volt

Q19. Which device protects circuit from overcurrent?

A) Cell
B) Ammeter
C) Fuse
D) Switch

✅ Answer: C) Fuse

Q20. Which material is used in filament of electric bulbs?

A) Iron
B) Copper
C) Tungsten
D) Aluminium

✅ Answer: C) Tungsten

Q21. Which one is a source of direct current (DC)?

A) Generator in power station
B) Dry cell
C) Transformer
D) Alternator

✅ Answer: B) Dry cell

Q22. Which is a secondary cell?

A) Dry cell
B) Lead acid battery
C) Primary cell
D) Solar cell

✅ Answer: B) Lead acid battery

Q23. An open circuit means:

A) Bulb glows
B) Current flows
C) No current flows
D) Switch is closed

✅ Answer: C) No current flows

Q24. Which of the following is a non-conductor?

A) Graphite
B) Wood
C) Aluminium
D) Copper

✅ Answer: B) Wood

Q25. Which is a device that stores electric energy?

A) Fuse
B) Capacitor
C) Switch
D) Transformer

✅ Answer: B) Capacitor

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