Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 141 · 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.True or false: to use old filament bulbs saves electricity. (a) True (b) False
2. 2.True or false: to use LED lamps wastes electricity. (a) True (b) False
3. 3.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 9 hours. How many watt-hours (Wh) are saved?
4. 4.🧾 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?
5. 5.🧾 A 1000 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
6. 6.🧾 A family uses 60 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
7. 7.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) a candle (c) an oil lamp (d) an LED lamp
8. 8.True or false: to leave the TV on standby wastes electricity. (a) False (b) True
9. 9.True or false: to use old filament bulbs wastes electricity. (a) False (b) True
10. 10.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
11. 11.Which of these saves electricity? (a) leave fridge door open (b) iron one shirt at a time (c) switch off empty rooms (d) leave the TV on standby
12. 12.🧾 A family uses 200 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
13. 13.🔍 Which is the odd one out? (a) switch off empty rooms (b) unplug idle chargers (c) leave the TV on standby (d) use daylight to read
14. 14.🔍 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) close the fridge quickly
15. 15.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 7 hours. How many watt-hours (Wh) are saved?
16. 16.True or false: to close the fridge quickly wastes electricity. (a) False (b) True
17. 17.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
18. 18.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
19. 19.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 7 hours. How many watt-hours (Wh) are saved?
20. 20.🧾 A family uses 120 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
21. 21.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 ampere (c) 1 watt (d) 1 kilowatt-hour (kWh)
22. 22.🔍 Which is the odd one out? (a) iron one shirt at a time (b) use daylight to read (c) run fans in empty rooms (d) leave fridge door open
23. 23.💡 Does it save or waste electricity to close the fridge quickly? (a) saves electricity (b) wastes electricity
24. 24.True or false: to run fans in empty rooms saves electricity. (a) True (b) False
25. 25.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
26. 26.True or false: to switch off empty rooms wastes electricity. (a) False (b) True
27. 27.Which of these saves electricity? (a) iron one shirt at a time (b) leave the TV on standby (c) use LED lamps (d) run fans in empty rooms
28. 28.Which of these wastes electricity? (a) set the AC to 24 °C (b) unplug idle chargers (c) switch off empty rooms (d) leave the TV on standby
29. 29.True or false: to unplug idle chargers wastes electricity. (a) True (b) False
30. 30.🔍 Which is the odd one out? (a) iron one shirt at a time (b) close the fridge quickly (c) switch off empty rooms (d) unplug idle chargers
31. 31.🧾 A family uses 130 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
32. 32.🔍 Which is the odd one out? (a) use LED lamps (b) leave fridge door open (c) use daylight to read (d) unplug idle chargers
33. 33.💡 Does it save or waste electricity to iron one shirt at a time? (a) saves electricity (b) wastes electricity
34. 34.🧾 A 50 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
35. 35.Which of these saves electricity? (a) leave the TV on standby (b) use old filament bulbs (c) use daylight to read (d) iron one shirt at a time
36. 36.Which of these saves electricity? (a) iron one shirt at a time (b) unplug idle chargers (c) run fans in empty rooms (d) leave fridge door open
37. 37.True or false: to iron one shirt at a time wastes electricity. (a) True (b) False
38. 38.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
39. 39.True or false: to unplug idle chargers saves electricity. (a) False (b) True
40. 40.Which of these wastes electricity? (a) use LED lamps (b) close the fridge quickly (c) use daylight to read (d) iron one shirt at a time

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