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1. Where is electricity usually generated before it goes to homes?
(A) In a battery
(B) In a power station
(C) In solar panels only
(D) In electric heaters
Answer: (B)
2. Why do power plants send electricity at a very high voltage through transmission lines?
(A) To reduce energy loss over long distances
(B) To make it safe to touch
(C) Because high voltage is cheaper
(D) To increase power output
Answer: (A)
3. What device is used to increase the voltage of electricity at a power station before it is sent out?
(A) Circuit breaker
(B) Transformer
(C) Fuse
(D) Switch
Answer: (B)
4. What is the role of a substation in delivering electricity to homes?
(A) To generate electricity
(B) To cool the electricity
(C) To reduce the voltage for local distribution
(D) To store electricity
Answer: (C)
5. After high-voltage electricity reaches a substation near your home, what happens next?
(A) It is sent through overhead power lines only
(B) Its voltage is lowered for local distribution
(C) It is stored in a battery for emergencies
(D) It is switched off
Answer: (B)
6. What do we call the large network of poles and wires that carries electricity from power plants to houses?
(A) Water system
(B) Power grid
(C) Road network
(D) Internet
Answer: (B)
7. Which of these items in your home measures how much electricity you use?
(A) Fuse
(B) Switch
(C) Electric meter
(D) Transformer
Answer: (C)
8. What is the purpose of the service panel (fuse box) in a house?
(A) To measure electricity
(B) To protect wires with fuses or breakers
(C) To increase voltage
(D) To store electricity
Answer: (B)
9. If one power station cannot meet the electricity demand, what can happen?
(A) Lights turn off everywhere
(B) Other stations send electricity through the power grid
(C) Homes immediately use solar power
(D) Nothing changes
Answer: (B)
10. What is the first thing electricity passes through when it enters your home?
(A) Electric meter
(B) Fuse
(C) Light bulb
(D) Refrigerator
Answer: (A)
11. What is the term for the wires that deliver electricity from substations to neighborhoods?
(A) Telephone lines
(C) Railway tracks
(D) Gas pipes
Answer: (B)
12. Why do some neighborhoods have no power poles and wires visible?
(A) Electricity is wireless there
(B) All homes use solar power instead
(C) Power lines are buried underground
(D) They have no electricity supply
Answer: (C)
13. What happens to the voltage of electricity in the small transformer near your house (often seen as a green box)?
(A) It is increased
(B) It stays the same
(C) It is reduced to a safe level for home use
(D) It is converted to direct current
Answer: (C)
14. Which path does electricity take after passing the household meter?
(A) To the service panel (fuse box) and then to outlets
(B) Directly to the light bulbs
(C) Back to the power plant
(D) To household batteries for storage
Answer: (A)
15. What is the "power grid"?
(A) A game played by electricians
(B) The system of connected power plants and lines that supply electricity
(C) A type of battery pack
(D) Another name for the fuse box
Answer: (B)
16. Which type of electric current is usually supplied to homes?
(A) Alternating current (AC)
(B) Direct current (DC)
(C) Battery current
(D) Solar current
Answer: (A)
17. Which wire is usually colored red or brown and carries current from the power supply to an appliance?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) Fuse wire
Answer: (A)
18. Which wire is usually at or near 0 volts and completes the circuit by carrying current back?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) Signal wire
Answer: (B)
19. Which wire is used for safety and is usually colored green or yellow-green?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) Communication wire
Answer: (C)
20. What is the purpose of the earth wire in an electrical appliance?
(A) To carry current to power the appliance
(B) To protect against electric shocks
(C) To supply data signals
(D) To measure the voltage
Answer: (B)
21. In a properly working appliance, which wires carry current during normal use?
(A) Live and neutral wires
(B) Only the live wire
(C) Live and earth wires
(D) Neutral and earth wires
Answer: (A)
22. Which of the following is a characteristic of the live wire?
(A) It is connected to the generator of the power station
(B) It is at 0 volts (no potential)
(C) It is always earthed (grounded)
(D) It has no color or marking
Answer: (A)
23. Which wire carries electricity back to the power station?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) Antenna wire
Answer: (B)
24. If the live wire accidentally touches the metal body of an appliance, which wire provides a safe path for the current?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) No wire does; the appliance will break
Answer: (C)
25. Which wire is directly connected to the earth at the main service panel in a house?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) Telephone wire
Answer: (C)
26. Why is the neutral wire usually not dangerous to touch under normal conditions?
(A) Because it carries current back to the source
(B) Because it is at about 0 volts relative to earth
(C) Because it is always insulated better
(D) It is just as dangerous as the live wire
Answer: (B)
27. What color is commonly used for the neutral wire in modern electrical cables?
(A) Red
(B) Black or blue
(C) Green
(D) Orange
Answer: (B)
28. What color is often used for the live wire under modern wiring standards?
(A) Green
(B) Blue
(C) Brown
(D) Yellow
Answer: (C)
29. Why do wires in the wall have plastic insulation?
(A) To reduce the cost of wiring
(B) To prevent short circuits and electric shocks
(C) To make them colorful and pretty
(D) To attract magnetic fields
Answer: (B)
30. What happens if the earth wire in an appliance is missing and a fault causes the live wire to touch the metal body?
(A) Nothing dangerous will happen
(B) The fuse will blow safely
(C) The metal body can become live and give a shock
(D) The appliance will run slower
Answer: (C)
31. Which of the following statements is true?
(A) The live wire is usually at 0 volts
(B) The neutral wire is usually at the mains voltage (around 220 V)
(C) The earth wire is only used for safety and carries no current under normal use
(D) The neutral wire is colored green
Answer: (C)
32. Inside a plug, the fuse is connected to which wire?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) It is not connected to any wire
Answer: (A)
33. What does the term "mains" generally refer to in electricity?
(A) Battery power
(B) The main electrical supply from the grid
(C) Solar panels on the roof
(D) A hand-crank generator
Answer: (B)
34. What is a plug used for in home electrical systems?
(A) Measuring electricity usage
(B) Connecting an appliance to a socket
(C) Breaking a circuit on demand
(D) Lighting an electric bulb
Answer: (B)
35. What is a socket (power outlet) used for?
(A) Storing electricity in the wall
(B) Connecting wires together permanently
(C) Providing a place to plug in appliances
(D) Measuring the current in a circuit
Answer: (C)
36. How many wires are typically connected inside a three-pin plug used at home?
(A) One
(B) Two
(C) Three
(D) Four
Answer: (C)
37. What component in a plug helps protect against too much current?
(A) The plastic body
(B) A fuse
(C) The earth pin
(D) The cable insulation
Answer: (B)
38. What does a switch do in an electrical circuit?
(A) It increases the current flow
(B) It opens or closes the circuit to turn devices on or off
(C) It measures the voltage
(D) It generates electricity
Answer: (B)
39. Why is it important to turn off the mains supply before repairing an appliance?
(A) To save electricity
(B) To prevent electric shock
(C) To complete a circuit
(D) To reduce water usage
Answer: (B)
40. Inside a plug, the fuse is connected to which wire?
(A) Live wire
(B) Neutral wire
(C) Earth wire
(D) No wire; it’s separate
Answer: (A)
41. What does a circuit breaker do?
(A) Increases the voltage
(B) Disconnects the circuit when current is too high
(C) Stores electricity for later use
(D) Changes alternating current (AC) to direct current (DC)
Answer: (B)
42. What is the main purpose of a fuse wire in a plug or appliance?
(A) To lower the voltage before use
(B) To break the circuit if the current becomes too high
(C) To increase the current during normal use
(D) To measure the power consumed
Answer: (B)
43. When an appliance is plugged into a socket, electricity flows to which of the following?
(A) The fuse box
(B) The earth connection
(C) The appliance (device) itself
(D) The main switchboard
Answer: (C)
44. Which of these is an example of an electrical switch?
(A) A light switch on a wall
(B) A piece of wire
(C) A battery
(D) A fuse
Answer: (A)
45. Why is the earth pin on many plugs longer than the other pins?
(A) To make the plug heavier
(B) So it connects first for safety if the plug is partly inserted
(C) For decoration
(D) It is not longer; this is a myth
Answer: (B)
46. What should you do if an electrical appliance begins to spark or smoke?
(A) Touch it to see what happens
(B) Keep using it as normal
(C) Unplug it and switch off the power immediately
(D) Pour water on it
Answer: (C)
47. What is the function of the main switch in a house’s electrical system?
(A) To pay the electricity bill
(B) To disconnect the entire house from the mains supply
(C) To measure the current in the main line
(D) To act as a giant fuse for the house
Answer: (B)
48. What happens if a light switch in a room is turned off?
(A) The circuit is opened and the light goes off
(B) The circuit is closed and the light goes on
(C) The light bulb burns out immediately
(D) The fuse in the switch blows
Answer: (A)
49. Which unit is used to measure electrical energy consumption on an electricity bill?
(A) Watt (W)
(B) Volt (V)
(C) Kilowatt-hour (kWh)
(D) Ampere-hour (Ah)
Answer: (C)
50. If an appliance uses 1 kilowatt of power for 1 hour, how many units of electricity does it consume?
(A) 0.1 unit
(B) 1 unit
(C) 10 units
(D) 100 units
Answer: (B)
51. What two values do you multiply to get the total energy used in kWh?
(A) Voltage (V) and current (A)
(B) Power (kW) and time (hours)
(C) Voltage (V) and time (h)
(D) Resistance (Ω) and current (A)
Answer: (B)
52. If a device uses 0.5 kW and runs for 4 hours, how many units of electricity does it consume?
(A) 2 kWh
(B) 4 kWh
(C) 0.5 kWh
(D) 8 kWh
Answer: (A)
53. Which of these will lower your electricity bill?
(A) Using appliances for longer time
(B) Using lower-power appliances or using them for shorter time
(C) Increasing the power of your appliances
(D) Leaving lights on even when not needed
Answer: (B)
54. Which of the following is multiplied by the number of units to find the total cost of electricity?
(A) The time the appliance was used
(B) The price per unit (cost per kWh)
(C) The power rating of the appliance
(D) The number of days in the billing period
Answer: (B)
55. If you double the time an appliance runs (keeping its power the same), what happens to the energy consumed?
(A) It stays the same
(B) It doubles
(C) It halves
(D) It slightly decreases
Answer: (B)
56. If the electricity rate is Rs 6 per unit and you use 3 kWh, what is the total cost?
(A) Rs 18
(B) Rs 9
(C) Rs 6
(D) Rs 3
Answer: (A)
57. Using a 1000 W (1 kW) heater for 2 hours at Rs 8 per unit of electricity costs how much?
(A) Rs 8
(B) Rs 16
(C) Rs 2
(D) Rs 10
Answer: (B)
58. Which situation uses more energy?
(A) A 60 W bulb for 10 hours
(B) A 120 W bulb for 3 hours
(C) Both use the same amount
(D) Cannot tell
Answer: (A)
59. If a 200 W fan is used for 5 hours at a rate of Rs 4 per unit, how much will it cost?
(A) Rs 4
(B) Rs 5
(C) Rs 20
(D) Rs 1
Answer: (A)
60. A 50 W LED runs for 20 hours. How many units of electricity does it consume?
(A) 1 unit
(B) 10 units
(C) 0.5 unit
(D) 2 units
Answer: (A)
61. A device uses 2 kW and runs for 3 hours. If electricity costs Rs 5 per unit, what is the cost?
(A) Rs 6
(B) Rs 30
(C) Rs 15
(D) Rs 10
Answer: (B)
62. Calculate the energy used by a 150 W device that runs for 4 hours.
(A) 0.6 kWh
(B) 6 kWh
(C) 60 kWh
(D) 0.06 kWh
Answer: (A)
63. If 1 unit of electricity costs Rs 7, how much does 0.5 kWh cost?
(A) Rs 3.5
(B) Rs 7
(C) Rs 14
(D) Rs 0.5
Answer: (A)
64. A TV of 120 W is used 5 hours a day for 10 days at a rate of Rs 5 per unit. What is the cost?
(A) Rs 30
(B) Rs 60
(C) Rs 6
(D) Rs 50
Answer: (A)
65. What is a short circuit?
(A) A circuit with a high-resistance appliance only
(B) A direct connection between live and neutral causing very high current
(C) A circuit with no current flow at all
(D) Another name for a broken wire
Answer: (B)
66. What can cause a short circuit in electrical wiring?
(A) Damaged insulation allowing wires to touch each other
(B) Using only one appliance at a time
(C) Turning off the main switch
(D) Having many switches in the circuit
Answer: (A)
67. Why are short circuits dangerous?
(A) They slow down the electricity supply
(B) They cause very high current which can overheat wires and start fires
(C) They clean the wires
(D) They make lights flicker but cause no harm
Answer: (B)
68. What should happen to the fuse if a short circuit occurs?
(A) Nothing; the fuse is not affected
(B) It should melt or blow to break the circuit
(C) It should heat up and melt later
(D) It should change color but stay in place
Answer: (B)
69. Which device is used to protect a circuit from too much current (like in a short circuit)?
(A) Resistor
(B) Battery
(C) Fuse or circuit breaker
(D) Switch
Answer: (C)
70. If too many appliances are plugged into one socket, what is the hazard?
(A) Brighter lights
(B) Overheating and possible fire
(C) Improved efficiency
(D) Extra free power
Answer: (B)
71. Which of these is a safe practice with electricity?
(A) Handling cords with wet hands
(B) Using electrical devices near water
(C) Keeping circuit breaker covers closed
(D) Covering outlets with metal foil
Answer: (C)
72. Why should you not handle electrical devices with wet hands?
(A) Water conducts electricity and can cause a shock
(B) It cools the device and stops it from working
(C) It has no effect on safety
(D) Wetness turns off the electricity
Answer: (A)
73. What is the purpose of earthing (grounding) in electrical systems?
(A) To store extra electricity in the ground
(B) To provide a safe path to the ground if a fault occurs
(C) To increase the voltage in the system
(D) To measure current in the wires
Answer: (B)
74. What might happen if a metal-bodied appliance is not earthed and a fault occurs?
(A) Nothing at all
(B) The metal body could become live and give an electric shock
(C) The appliance will use less power
(D) The appliance will run faster
Answer: (B)
75. What should you do if you see sparks or smoke coming from an electrical appliance?
(A) Ignore it and keep using the appliance
(B) Switch it off and unplug it immediately
(C) Pour water on it to cool it down
(D) Plug in more devices to balance the circuit
Answer: (B)
76. Which of the following is a safe practice with electricity?
(A) Touching a light bulb while the switch is on
(B) Pulling a plug out by its cord quickly
(C) Unplugging an appliance before repairing it
(D) Using a metal object to retrieve a dropped plug
Answer: (C)
77. What is likely to happen if live and neutral wires touch each other accidentally?
(A) The lamp becomes brighter
(B) A short circuit occurs
(C) Electricity stops completely but safely
(D) Nothing at all happens
Answer: (B)
78. If you accidentally touch a live wire, what could happen?
(A) You would feel an electric shock
(B) You start generating electricity in your body
(C) You become insulated and safe
(D) You hear music from the wire
Answer: (A)
79. What role does a fuse play during an electrical overload?
(A) It boosts the current through the circuit
(B) It lights up a warning lamp
(C) It melts to break the circuit and stop the current
(D) It reduces the voltage in the circuit
Answer: (C)
80. Why is it dangerous to use a damaged (frayed) electrical cord?
(A) It is actually safer to use
(B) It can cause a short circuit or an electric shock
(C) Nothing happens; it still works fine
(D) It provides more power to the appliance
Answer: (B)
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