Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 921 · 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 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
2. 2.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
3. 3.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 kilowatt-hour (kWh) (c) 1 ampere (d) 1 watt
4. 4.True or false: to run fans in empty rooms saves electricity. (a) False (b) True
5. 5.Which of these wastes electricity? (a) use LED lamps (b) set the AC to 24 °C (c) switch off empty rooms (d) run fans in empty rooms
6. 6.🧾 A 250 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
7. 7.🔍 Which is the odd one out? (a) iron one shirt at a time (b) run fans in empty rooms (c) use daylight to read (d) leave fridge door open
8. 8.🔍 Which is the odd one out? (a) use daylight to read (b) use LED lamps (c) iron one shirt at a time (d) unplug idle chargers
9. 9.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
10. 10.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 4 hours. How many watt-hours (Wh) are saved?
11. 11.🧾 A family uses 50 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
12. 12.🧾 A family uses 80 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
13. 13.💡 Does it save or waste electricity to use LED lamps? (a) wastes electricity (b) saves electricity
14. 14.Which of these wastes electricity? (a) close the fridge quickly (b) unplug idle chargers (c) set the AC to 24 °C (d) iron one shirt at a time
15. 15.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) run fans in empty rooms (c) use LED lamps (d) unplug idle chargers
16. 16.🔍 Which is the odd one out? (a) use old filament bulbs (b) leave the TV on standby (c) switch off empty rooms (d) run fans in empty rooms
17. 17.🔍 Which is the odd one out? (a) leave the TV on standby (b) use daylight to read (c) set the AC to 24 °C (d) use LED lamps
18. 18.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) an LED lamp (c) an oil lamp (d) a candle
19. 19.Which of these wastes electricity? (a) set the AC to 24 °C (b) use daylight to read (c) leave the TV on standby (d) unplug idle chargers
20. 20.🧾 A 100 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
21. 21.🧾 A family uses 100 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
22. 22.🔍 Which is the odd one out? (a) use LED lamps (b) close the fridge quickly (c) use daylight to read (d) use old filament bulbs
23. 23.🧾 A 200 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
24. 24.True or false: to leave the TV on standby wastes electricity. (a) True (b) False
25. 25.True or false: to switch off empty rooms saves electricity. (a) True (b) False
26. 26.Which of these wastes electricity? (a) close the fridge quickly (b) leave fridge door open (c) use LED lamps (d) use daylight to read
27. 27.True or false: to switch off empty rooms wastes electricity. (a) False (b) True
28. 28.🧾 A 50 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
29. 29.🔍 Which is the odd one out? (a) leave fridge door open (b) leave the TV on standby (c) use LED lamps (d) iron one shirt at a time
30. 30.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
31. 31.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
32. 32.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
33. 33.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
34. 34.🧾 A family uses 70 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
35. 35.Which of these wastes electricity? (a) switch off empty rooms (b) use daylight to read (c) set the AC to 24 °C (d) use old filament bulbs
36. 36.True or false: to use old filament bulbs wastes electricity. (a) True (b) False
37. 37.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
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 8 hours. How many watt-hours (Wh) are saved?
39. 39.Which of these saves electricity? (a) leave fridge door open (b) close the fridge quickly (c) iron one shirt at a time (d) leave the TV on standby
40. 40.Which of these saves electricity? (a) leave the TV on standby (b) use old filament bulbs (c) iron one shirt at a time (d) switch off empty rooms

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