Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 10 · 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.🔍 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
2. 2.Which of these wastes electricity? (a) switch off empty rooms (b) set the AC to 24 °C (c) unplug idle chargers (d) iron one shirt at a time
3. 3.True or false: to leave fridge door open wastes electricity. (a) False (b) True
4. 4.True or false: to set the AC to 24 °C wastes electricity. (a) False (b) True
5. 5.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 ampere (c) 1 watt (d) 1 kilowatt-hour (kWh)
6. 6.🧾 Which lamp gives the same light for the least power? (a) an oil lamp (b) an LED lamp (c) a candle (d) a filament bulb
7. 7.🔍 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
8. 8.True or false: to use LED lamps wastes electricity. (a) False (b) True
9. 9.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
10. 10.🧾 A 50 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
11. 11.🧾 A family uses 50 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
12. 12.🧾 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?
13. 13.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
14. 14.🧾 A 1500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
15. 15.True or false: to use old filament bulbs wastes electricity. (a) False (b) True
16. 16.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 6 hours. How many watt-hours (Wh) are saved?
17. 17.True or false: to set the AC to 24 °C saves electricity. (a) False (b) True
18. 18.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
19. 19.Which of these saves electricity? (a) run fans in empty rooms (b) use old filament bulbs (c) leave fridge door open (d) use daylight to read
20. 20.True or false: to use daylight to read saves electricity. (a) False (b) True
21. 21.🔍 Which is the odd one out? (a) leave fridge door open (b) leave the TV on standby (c) run fans in empty rooms (d) set the AC to 24 °C
22. 22.🔍 Which is the odd one out? (a) run fans in empty rooms (b) switch off empty rooms (c) leave the TV on standby (d) leave fridge door open
23. 23.🧾 A 200 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
24. 24.Which of these wastes electricity? (a) use daylight to read (b) use LED lamps (c) close the fridge quickly (d) leave the TV on standby
25. 25.🧾 A 2000 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
26. 26.🧾 A 500 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
27. 27.Which of these wastes electricity? (a) switch off empty rooms (b) use daylight to read (c) use old filament bulbs (d) use LED lamps
28. 28.Which of these saves electricity? (a) iron one shirt at a time (b) unplug idle chargers (c) use old filament bulbs (d) leave the TV on standby
29. 29.Which of these wastes electricity? (a) unplug idle chargers (b) set the AC to 24 °C (c) run fans in empty rooms (d) switch off empty rooms
30. 30.💡 Does it save or waste electricity to iron one shirt at a time? (a) saves electricity (b) wastes electricity
31. 31.💡 Does it save or waste electricity to leave fridge door open? (a) wastes electricity (b) saves electricity
32. 32.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
33. 33.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
34. 34.🧾 A family uses 60 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
35. 35.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
36. 36.🧾 A family uses 40 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
37. 37.True or false: to switch off empty rooms saves 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 9 hours. How many watt-hours (Wh) are saved?
39. 39.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 4 hours. How many watt-hours (Wh) are saved?
40. 40.🧾 A family uses 110 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?

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