← Electricity units and saving power lesson New set →

Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 490 · 40 questions
TalentJR

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.

NameDateTime takenScore ___ / 40
  1. 1.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
  2. 2.💡 Does it save or waste electricity to set the AC to 24 °C? (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.🧾 A family uses 40 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  5. 5.True or false: to run fans in empty rooms wastes electricity. (a) True (b) False
  6. 6.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
  7. 7.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) close the fridge quickly (c) unplug idle chargers (d) run fans in empty rooms
  8. 8.💡 Does it save or waste electricity to leave the TV on standby? (a) wastes electricity (b) saves electricity
  9. 9.True or false: to use daylight to read saves electricity. (a) False (b) True
  10. 10.True or false: to unplug idle chargers wastes electricity. (a) True (b) False
  11. 11.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
  12. 12.🧾 A 50 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  13. 13.Which of these wastes electricity? (a) close the fridge quickly (b) switch off empty rooms (c) unplug idle chargers (d) run fans in empty rooms
  14. 14.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
  15. 15.True or false: to leave fridge door open wastes electricity. (a) True (b) False
  16. 16.🔍 Which is the odd one out? (a) switch off empty rooms (b) iron one shirt at a time (c) use daylight to read (d) unplug idle chargers
  17. 17.Which of these saves electricity? (a) leave the TV on standby (b) use LED lamps (c) run fans in empty rooms (d) leave fridge door open
  18. 18.True or false: to close the fridge quickly wastes electricity. (a) True (b) False
  19. 19.🔍 Which is the odd one out? (a) iron one shirt at a time (b) switch off empty rooms (c) leave the TV on standby (d) use old filament bulbs
  20. 20.🔍 Which is the odd one out? (a) use old filament bulbs (b) use daylight to read (c) set the AC to 24 °C (d) switch off empty rooms
  21. 21.🧾 A 1500 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  22. 22.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) switch off empty rooms (c) use LED lamps (d) leave fridge door open
  23. 23.🧾 A 50 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  24. 24.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  25. 25.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 8 hours. How many watt-hours (Wh) are saved?
  26. 26.🧾 A family uses 50 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  27. 27.🧾 A 1000 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  28. 28.Which of these saves electricity? (a) use daylight to read (b) leave the TV on standby (c) use old filament bulbs (d) iron one shirt at a time
  29. 29.True or false: to use old filament bulbs wastes electricity. (a) True (b) False
  30. 30.Which of these saves electricity? (a) use old filament bulbs (b) unplug idle chargers (c) run fans in empty rooms (d) iron one shirt at a time
  31. 31.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
  32. 32.🧾 A 500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  33. 33.🧾 A 50 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  34. 34.🧾 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?
  35. 35.True or false: to use LED lamps wastes electricity. (a) False (b) True
  36. 36.🔍 Which is the odd one out? (a) use old filament bulbs (b) set the AC to 24 °C (c) iron one shirt at a time (d) leave fridge door open
  37. 37.🧾 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?
  38. 38.Which of these wastes electricity? (a) switch off empty rooms (b) iron one shirt at a time (c) close the fridge quickly (d) unplug idle chargers
  39. 39.🧾 A 100 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  40. 40.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity

Answer key

  1. wastes electricity
  2. saves electricity
  3. 1 kilowatt-hour (kWh)
  4. 200
  5. True
  6. 340
  7. run fans in empty rooms
  8. wastes electricity
  9. True
  10. False
  11. saves electricity
  12. 0.2
  13. run fans in empty rooms
  14. True
  15. True
  16. iron one shirt at a time
  17. use LED lamps
  18. False
  19. switch off empty rooms
  20. use old filament bulbs
  21. 9
  22. leave fridge door open
  23. 0.5
  24. 1
  25. 272
  26. 350
  27. 4
  28. use daylight to read
  29. True
  30. unplug idle chargers
  31. saves electricity
  32. 2
  33. 0.4
  34. 567
  35. False
  36. set the AC to 24 °C
  37. 441
  38. iron one shirt at a time
  39. 0.6
  40. wastes electricity

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