← Electricity units and saving power lesson New set →

Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 8 · 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.🔍 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
  2. 2.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  3. 3.🔍 Which is the odd one out? (a) run fans in empty rooms (b) leave fridge door open (c) iron one shirt at a time (d) close the fridge quickly
  4. 4.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
  5. 5.Which of these saves electricity? (a) run fans in empty rooms (b) use old filament bulbs (c) close the fridge quickly (d) leave fridge door open
  6. 6.🧾 Which lamp gives the same light for the least power? (a) a candle (b) an oil lamp (c) an LED lamp (d) a filament bulb
  7. 7.🔍 Which is the odd one out? (a) switch off empty rooms (b) run fans in empty rooms (c) leave the TV on standby (d) use old filament bulbs
  8. 8.True or false: to run fans in empty rooms saves electricity. (a) False (b) True
  9. 9.🔍 Which is the odd one out? (a) switch off empty rooms (b) use daylight to read (c) set the AC to 24 °C (d) use old filament bulbs
  10. 10.🧾 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?
  11. 11.True or false: to leave the TV on standby saves electricity. (a) False (b) True
  12. 12.🧾 A family uses 30 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  13. 13.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 9 hours. How many watt-hours (Wh) are saved?
  14. 14.True or false: to use LED lamps saves electricity. (a) False (b) True
  15. 15.🧾 A 500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  16. 16.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
  17. 17.🧾 A 2000 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  18. 18.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 kilowatt-hour (kWh) (c) 1 ampere (d) 1 volt
  19. 19.🧾 A 1000 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  20. 20.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
  21. 21.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  22. 22.Which of these saves electricity? (a) leave fridge door open (b) run fans in empty rooms (c) iron one shirt at a time (d) use LED lamps
  23. 23.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  24. 24.🧾 A family uses 50 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
  25. 25.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 5 hours. How many watt-hours (Wh) are saved?
  26. 26.🧾 A 1000 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  27. 27.True or false: to close the fridge quickly saves electricity. (a) True (b) False
  28. 28.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
  29. 29.🧾 A 1500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  30. 30.Which of these wastes electricity? (a) use daylight to read (b) iron one shirt at a time (c) set the AC to 24 °C (d) switch off empty rooms
  31. 31.Which of these saves electricity? (a) run fans in empty rooms (b) set the AC to 24 °C (c) use old filament bulbs (d) leave fridge door open
  32. 32.🧾 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?
  33. 33.Which of these saves electricity? (a) use old filament bulbs (b) switch off empty rooms (c) iron one shirt at a time (d) leave the TV on standby
  34. 34.True or false: to unplug idle chargers wastes electricity. (a) True (b) False
  35. 35.🧾 A 50 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  36. 36.Which of these wastes electricity? (a) leave fridge door open (b) switch off empty rooms (c) use LED lamps (d) unplug idle chargers
  37. 37.True or false: to use old filament bulbs wastes electricity. (a) True (b) False
  38. 38.Which of these wastes electricity? (a) close the fridge quickly (b) leave the TV on standby (c) set the AC to 24 °C (d) use LED lamps
  39. 39.True or false: to use old filament bulbs saves electricity. (a) False (b) True
  40. 40.True or false: to leave fridge door open saves electricity. (a) False (b) True

Answer key

  1. leave fridge door open
  2. 0.4
  3. close the fridge quickly
  4. wastes electricity
  5. close the fridge quickly
  6. an LED lamp
  7. switch off empty rooms
  8. False
  9. use old filament bulbs
  10. 567
  11. False
  12. 120
  13. 459
  14. True
  15. 2
  16. wastes electricity
  17. 12
  18. 1 kilowatt-hour (kWh)
  19. 4
  20. saves electricity
  21. saves electricity
  22. use LED lamps
  23. 1
  24. 300
  25. 255
  26. 2
  27. True
  28. saves electricity
  29. 6
  30. iron one shirt at a time
  31. set the AC to 24 °C
  32. 102
  33. switch off empty rooms
  34. False
  35. 0.25
  36. leave fridge door open
  37. True
  38. leave the TV on standby
  39. False
  40. False

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