Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 420 · 40 questions

Remember (Watts × hours ÷ 1000): Units (kWh) = watts × hours ÷ 1000. Bill = units × price per unit (e.g. 150 units × ₹6 = ₹900). Save: switch off, LED lamps, daylight, no standby, close the fridge quickly.

1. 1.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
2. 2.🔍 Which is the odd one out? (a) leave the TV on standby (b) use daylight to read (c) use LED lamps (d) set the AC to 24 °C
3. 3.🧾 A 100 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
4. 4.🔍 Which is the odd one out? (a) run fans in empty rooms (b) use old filament bulbs (c) leave the TV on standby (d) switch off empty rooms
5. 5.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
6. 6.🧾 A family uses 20 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
7. 7.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 volt (c) 1 kilowatt-hour (kWh) (d) 1 ampere
8. 8.Which of these wastes electricity? (a) unplug idle chargers (b) close the fridge quickly (c) use LED lamps (d) use old filament bulbs
9. 9.Which of these saves electricity? (a) iron one shirt at a time (b) leave the TV on standby (c) run fans in empty rooms (d) close the fridge quickly
10. 10.🔍 Which is the odd one out? (a) use old filament bulbs (b) run fans in empty rooms (c) leave the TV on standby (d) use daylight to read
11. 11.True or false: to leave fridge door open wastes electricity. (a) False (b) True
12. 12.True or false: to use LED lamps wastes electricity. (a) True (b) False
13. 13.True or false: to use daylight to read saves electricity. (a) True (b) False
14. 14.🧾 A 200 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
15. 15.🔍 Which is the odd one out? (a) close the fridge quickly (b) switch off empty rooms (c) unplug idle chargers (d) leave fridge door open
16. 16.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave fridge door open (c) leave the TV on standby (d) use LED lamps
17. 17.Which of these saves electricity? (a) use old filament bulbs (b) leave the TV on standby (c) leave fridge door open (d) use daylight to read
18. 18.🧾 A 250 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
19. 19.🔍 Which is the odd one out? (a) unplug idle chargers (b) run fans in empty rooms (c) use daylight to read (d) close the fridge quickly
20. 20.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) an oil lamp (c) a candle (d) an LED lamp
21. 21.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
22. 22.🔍 Which is the odd one out? (a) switch off empty rooms (b) use LED lamps (c) iron one shirt at a time (d) close the fridge quickly
23. 23.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave the TV on standby (c) run fans in empty rooms (d) set the AC to 24 °C
24. 24.🔍 Which is the odd one out? (a) run fans in empty rooms (b) use old filament bulbs (c) unplug idle chargers (d) leave the TV on standby
25. 25.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
26. 26.🧾 A 100 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
27. 27.True or false: to set the AC to 24 °C saves electricity. (a) True (b) False
28. 28.🧾 A 500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
29. 29.Which of these wastes electricity? (a) run fans in empty rooms (b) use daylight to read (c) switch off empty rooms (d) close the fridge quickly
30. 30.💡 Does it save or waste electricity to run fans in empty rooms? (a) saves electricity (b) wastes electricity
31. 31.Which of these saves electricity? (a) leave fridge door open (b) iron one shirt at a time (c) leave the TV on standby (d) use LED lamps
32. 32.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
33. 33.Which of these wastes electricity? (a) switch off empty rooms (b) unplug idle chargers (c) leave the TV on standby (d) set the AC to 24 °C
34. 34.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
35. 35.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 6 hours. How many watt-hours (Wh) are saved?
36. 36.Which of these saves electricity? (a) unplug idle chargers (b) iron one shirt at a time (c) use old filament bulbs (d) leave fridge door open
37. 37.🔍 Which is the odd one out? (a) use old filament bulbs (b) close the fridge quickly (c) run fans in empty rooms (d) iron one shirt at a time
38. 38.💡 Does it save or waste electricity to iron one shirt at a time? (a) saves electricity (b) wastes electricity
39. 39.🧾 A family uses 160 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
40. 40.True or false: to run fans in empty rooms wastes electricity. (a) False (b) True

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids