Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 150 · 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 of these saves electricity? (a) run fans in empty rooms (b) leave the TV on standby (c) iron one shirt at a time (d) switch off empty rooms
2. 2.True or false: to use LED lamps wastes electricity. (a) False (b) True
3. 3.🧾 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?
4. 4.🔍 Which is the odd one out? (a) leave fridge door open (b) run fans in empty rooms (c) use old filament bulbs (d) use daylight to read
5. 5.🔍 Which is the odd one out? (a) switch off empty rooms (b) close the fridge quickly (c) leave the TV on standby (d) unplug idle chargers
6. 6.Which of these saves electricity? (a) leave the TV on standby (b) iron one shirt at a time (c) run fans in empty rooms (d) use LED lamps
7. 7.🔍 Which is the odd one out? (a) unplug idle chargers (b) use old filament bulbs (c) run fans in empty rooms (d) iron one shirt at a time
8. 8.True or false: to use daylight to read saves electricity. (a) True (b) False
9. 9.💡 Does it save or waste electricity to leave the TV on standby? (a) wastes electricity (b) saves electricity
10. 10.🔍 Which is the odd one out? (a) use old filament bulbs (b) leave the TV on standby (c) close the fridge quickly (d) run fans in empty rooms
11. 11.True or false: to close the fridge quickly saves electricity. (a) False (b) True
12. 12.Which of these wastes electricity? (a) close the fridge quickly (b) use LED lamps (c) leave the TV on standby (d) unplug idle chargers
13. 13.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 kilowatt-hour (kWh) (c) 1 ampere (d) 1 watt
14. 14.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 9 hours. How many watt-hours (Wh) are saved?
15. 15.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
16. 16.True or false: to switch off empty rooms wastes electricity. (a) True (b) False
17. 17.🧾 A 100 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
18. 18.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
19. 19.💡 Does it save or waste electricity to run fans in empty rooms? (a) saves electricity (b) wastes electricity
20. 20.💡 Does it save or waste electricity to close the fridge quickly? (a) saves electricity (b) wastes electricity
21. 21.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
22. 22.🧾 A family uses 200 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
23. 23.🧾 Which lamp gives the same light for the least power? (a) an LED lamp (b) a candle (c) a filament bulb (d) an oil lamp
24. 24.🧾 A 200 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
25. 25.True or false: to close the fridge quickly wastes electricity. (a) True (b) False
26. 26.True or false: to leave the TV on standby saves electricity. (a) True (b) False
27. 27.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
28. 28.True or false: to set the AC to 24 °C wastes electricity. (a) True (b) False
29. 29.🧾 A family uses 130 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
30. 30.🧾 A family uses 200 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
31. 31.True or false: to unplug idle chargers saves electricity. (a) False (b) True
32. 32.🧾 A 50 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
33. 33.🧾 A 1000 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
34. 34.True or false: to iron one shirt at a time saves electricity. (a) False (b) True
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 4 hours. How many watt-hours (Wh) are saved?
36. 36.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
37. 37.💡 Does it save or waste electricity to iron one shirt at a time? (a) saves electricity (b) wastes electricity
38. 38.🧾 A 1000 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
39. 39.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 7 hours. How many watt-hours (Wh) are saved?
40. 40.🔍 Which is the odd one out? (a) use LED lamps (b) set the AC to 24 °C (c) iron one shirt at a time (d) unplug idle chargers

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