← Electricity units and saving power lesson New set →

Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 927 · 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 leave fridge door open wastes electricity. (a) False (b) True
  2. 2.🧾 A family uses 90 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  3. 3.🧾 A family uses 150 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  4. 4.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
  5. 5.🧾 Which lamp gives the same light for the least power? (a) a candle (b) a filament bulb (c) an LED lamp (d) an oil lamp
  6. 6.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
  7. 7.True or false: to use LED lamps saves electricity. (a) False (b) True
  8. 8.🧾 A 2000 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  9. 9.Which of these wastes electricity? (a) leave the TV on standby (b) set the AC to 24 °C (c) use LED lamps (d) close the fridge quickly
  10. 10.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
  11. 11.🧾 A family uses 130 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  12. 12.🧾 A family uses 20 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  13. 13.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 8 hours. How many watt-hours (Wh) are saved?
  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 1 hour. How many watt-hours (Wh) are saved?
  15. 15.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
  16. 16.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
  17. 17.🔍 Which is the odd one out? (a) run fans in empty rooms (b) leave the TV on standby (c) leave fridge door open (d) switch off empty rooms
  18. 18.True or false: to run fans in empty rooms wastes electricity. (a) False (b) True
  19. 19.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
  20. 20.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  21. 21.🧾 A family uses 80 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  22. 22.Which of these wastes electricity? (a) use LED lamps (b) iron one shirt at a time (c) use daylight to read (d) set the AC to 24 °C
  23. 23.True or false: to use old filament bulbs wastes electricity. (a) False (b) True
  24. 24.🔍 Which is the odd one out? (a) close the fridge quickly (b) iron one shirt at a time (c) use daylight to read (d) unplug idle chargers
  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 100 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  27. 27.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
  28. 28.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
  29. 29.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
  30. 30.Which of these saves electricity? (a) run fans in empty rooms (b) leave fridge door open (c) leave the TV on standby (d) use LED lamps
  31. 31.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 kilowatt-hour (kWh) (c) 1 watt (d) 1 volt
  32. 32.🧾 A 500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  33. 33.🧾 A 50 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  34. 34.Which of these wastes electricity? (a) use old filament bulbs (b) use LED lamps (c) close the fridge quickly (d) use daylight to read
  35. 35.True or false: to switch off empty rooms saves electricity. (a) False (b) True
  36. 36.🧾 A 1500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  37. 37.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
  38. 38.🧾 A 50 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  39. 39.🧾 A 100 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  40. 40.Which of these wastes electricity? (a) leave fridge door open (b) unplug idle chargers (c) close the fridge quickly (d) switch off empty rooms

Answer key

  1. True
  2. 720
  3. 1050
  4. 255
  5. an LED lamp
  6. 850
  7. True
  8. 16
  9. leave the TV on standby
  10. saves electricity
  11. 1170
  12. 180
  13. 504
  14. 63
  15. saves electricity
  16. wastes electricity
  17. switch off empty rooms
  18. True
  19. True
  20. saves electricity
  21. 400
  22. iron one shirt at a time
  23. True
  24. iron one shirt at a time
  25. 420
  26. 1
  27. wastes electricity
  28. saves electricity
  29. wastes electricity
  30. use LED lamps
  31. 1 kilowatt-hour (kWh)
  32. 5
  33. 0.25
  34. use old filament bulbs
  35. True
  36. 15
  37. 102
  38. 0.5
  39. 0.6
  40. leave fridge door open

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