← Electricity units and saving power lesson New set →

Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 475 · 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.True or false: to switch off empty rooms saves electricity. (a) True (b) False
  2. 2.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) leave the TV on standby (c) leave fridge door open (d) use old filament bulbs
  3. 3.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
  4. 4.🔍 Which is the odd one out? (a) unplug idle chargers (b) close the fridge quickly (c) use old filament bulbs (d) switch off empty rooms
  5. 5.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
  6. 6.True or false: to use daylight to read saves electricity. (a) True (b) False
  7. 7.🧾 A 250 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  8. 8.🧾 A 2000 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  9. 9.🧾 A 200 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  10. 10.Which of these saves electricity? (a) use old filament bulbs (b) run fans in empty rooms (c) switch off empty rooms (d) leave fridge door open
  11. 11.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
  12. 12.True or false: to close the fridge quickly wastes electricity. (a) False (b) True
  13. 13.🔍 Which is the odd one out? (a) leave fridge door open (b) switch off empty rooms (c) iron one shirt at a time (d) leave the TV on standby
  14. 14.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
  15. 15.True or false: to close the fridge quickly saves electricity. (a) False (b) True
  16. 16.True or false: to leave the TV on standby saves electricity. (a) False (b) True
  17. 17.🧾 Which lamp gives the same light for the least power? (a) a candle (b) an LED lamp (c) a filament bulb (d) an oil lamp
  18. 18.Which of these saves electricity? (a) use old filament bulbs (b) unplug idle chargers (c) iron one shirt at a time (d) run fans in empty rooms
  19. 19.Which of these saves electricity? (a) iron one shirt at a time (b) set the AC to 24 °C (c) leave the TV on standby (d) leave fridge door open
  20. 20.True or false: to set the AC to 24 °C saves electricity. (a) True (b) False
  21. 21.🧾 A family uses 160 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  22. 22.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
  23. 23.Which of these saves electricity? (a) use daylight to read (b) leave the TV on standby (c) leave fridge door open (d) use old filament bulbs
  24. 24.🧾 A family uses 110 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  25. 25.🧾 A family uses 60 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  26. 26.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
  27. 27.🧾 A family uses 40 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  28. 28.🧾 A 250 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  29. 29.🧾 A family uses 110 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  30. 30.🧾 A 100 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  31. 31.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
  32. 32.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
  33. 33.🔍 Which is the odd one out? (a) switch off empty rooms (b) use daylight to read (c) run fans in empty rooms (d) unplug idle chargers
  34. 34.Which of these wastes electricity? (a) set the AC to 24 °C (b) close the fridge quickly (c) switch off empty rooms (d) use old filament bulbs
  35. 35.True or false: to leave fridge door open wastes electricity. (a) False (b) True
  36. 36.🔍 Which is the odd one out? (a) unplug idle chargers (b) set the AC to 24 °C (c) iron one shirt at a time (d) switch off empty rooms
  37. 37.🧾 A family uses 90 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  38. 38.🔍 Which is the odd one out? (a) switch off empty rooms (b) use daylight to read (c) leave fridge door open (d) close the fridge quickly
  39. 39.Which of these wastes electricity? (a) use daylight to read (b) switch off empty rooms (c) unplug idle chargers (d) leave the TV on standby
  40. 40.🧾 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?

Answer key

  1. True
  2. set the AC to 24 °C
  3. saves electricity
  4. use old filament bulbs
  5. saves electricity
  6. True
  7. 2
  8. 20
  9. 1.2
  10. switch off empty rooms
  11. 85
  12. False
  13. switch off empty rooms
  14. saves electricity
  15. True
  16. False
  17. an LED lamp
  18. unplug idle chargers
  19. set the AC to 24 °C
  20. True
  21. 1280
  22. wastes electricity
  23. use daylight to read
  24. 990
  25. 420
  26. 510
  27. 320
  28. 1.5
  29. 550
  30. 0.2
  31. wastes electricity
  32. wastes electricity
  33. run fans in empty rooms
  34. use old filament bulbs
  35. True
  36. iron one shirt at a time
  37. 720
  38. leave fridge door open
  39. leave the TV on standby
  40. 459

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