Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 417 · 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 unplug idle chargers wastes electricity. (a) True (b) False
2. 2.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 ampere (c) 1 volt (d) 1 kilowatt-hour (kWh)
3. 3.🧾 Which lamp gives the same light for the least power? (a) a candle (b) a filament bulb (c) an oil lamp (d) an LED lamp
4. 4.🧾 A 50 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
5. 5.🔍 Which is the odd one out? (a) leave fridge door open (b) use LED lamps (c) use old filament bulbs (d) leave the TV on standby
6. 6.🧾 A family uses 120 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
7. 7.Which of these wastes electricity? (a) close the fridge quickly (b) unplug idle chargers (c) set the AC to 24 °C (d) leave the TV on standby
8. 8.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
9. 9.🔍 Which is the odd one out? (a) leave the TV on standby (b) iron one shirt at a time (c) use old filament bulbs (d) use daylight to read
10. 10.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
11. 11.🧾 A 1500 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
12. 12.Which of these saves electricity? (a) run fans in empty rooms (b) use old filament bulbs (c) unplug idle chargers (d) leave fridge door open
13. 13.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
14. 14.Which of these saves electricity? (a) leave fridge door open (b) leave the TV on standby (c) use daylight to read (d) run fans in empty rooms
15. 15.🧾 A family uses 20 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
16. 16.🔍 Which is the odd one out? (a) unplug idle chargers (b) use old filament bulbs (c) use daylight to read (d) close the fridge quickly
17. 17.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) use daylight to read (c) switch off empty rooms (d) leave fridge door open
18. 18.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
19. 19.True or false: to iron one shirt at a time saves electricity. (a) False (b) True
20. 20.Which of these wastes electricity? (a) switch off empty rooms (b) use daylight to read (c) iron one shirt at a time (d) unplug idle chargers
21. 21.🧾 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?
22. 22.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
23. 23.🧾 A family uses 50 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
24. 24.🔍 Which is the odd one out? (a) leave fridge door open (b) leave the TV on standby (c) set the AC to 24 °C (d) iron one shirt at a time
25. 25.🧾 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?
26. 26.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
27. 27.🧾 A 1000 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
28. 28.🔍 Which is the odd one out? (a) switch off empty rooms (b) iron one shirt at a time (c) use daylight to read (d) set the AC to 24 °C
29. 29.Which of these saves electricity? (a) iron one shirt at a time (b) set the AC to 24 °C (c) run fans in empty rooms (d) leave the TV on standby
30. 30.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
31. 31.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
32. 32.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) use LED lamps (c) run fans in empty rooms (d) unplug idle chargers
33. 33.Which of these wastes electricity? (a) use old filament bulbs (b) close the fridge quickly (c) set the AC to 24 °C (d) switch off empty rooms
34. 34.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
35. 35.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
36. 36.🧾 A family uses 80 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
37. 37.True or false: to leave fridge door open wastes electricity. (a) False (b) True
38. 38.🧾 A 1500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
39. 39.🧾 A family uses 140 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
40. 40.🧾 A 50 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =

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