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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 539 · 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.

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  1. 1.🧾 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
  2. 2.True or false: to iron one shirt at a time saves electricity. (a) True (b) False
  3. 3.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 volt (c) 1 ampere (d) 1 kilowatt-hour (kWh)
  4. 4.🔍 Which is the odd one out? (a) switch off empty rooms (b) use daylight to read (c) use old filament bulbs (d) close the fridge quickly
  5. 5.🧾 A family uses 90 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  6. 6.Which of these saves electricity? (a) leave fridge door open (b) close the fridge quickly (c) use old filament bulbs (d) leave the TV on standby
  7. 7.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
  8. 8.🧾 A family uses 20 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  9. 9.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
  10. 10.🧾 A 2000 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  11. 11.Which of these saves electricity? (a) switch off empty rooms (b) use old filament bulbs (c) run fans in empty rooms (d) leave the TV on standby
  12. 12.True or false: to set the AC to 24 °C saves electricity. (a) False (b) True
  13. 13.🧾 A 100 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  14. 14.True or false: to leave fridge door open wastes electricity. (a) False (b) True
  15. 15.🧾 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?
  16. 16.🧾 A family uses 30 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  17. 17.🔍 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) run fans in empty rooms
  18. 18.True or false: to switch off empty rooms saves electricity. (a) False (b) True
  19. 19.True or false: to use daylight to read wastes electricity. (a) False (b) True
  20. 20.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
  21. 21.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
  22. 22.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 8 hours. How many watt-hours (Wh) are saved?
  23. 23.🧾 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?
  24. 24.🧾 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?
  25. 25.Which of these saves electricity? (a) set the AC to 24 °C (b) leave the TV on standby (c) use old filament bulbs (d) leave fridge door open
  26. 26.💡 Does it save or waste electricity to use LED lamps? (a) wastes electricity (b) saves electricity
  27. 27.🧾 A 1500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  28. 28.🧾 A 1000 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  29. 29.True or false: to use old filament bulbs saves electricity. (a) True (b) False
  30. 30.Which of these saves electricity? (a) use old filament bulbs (b) run fans in empty rooms (c) use daylight to read (d) leave the TV on standby
  31. 31.🧾 A family uses 60 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
  32. 32.🔍 Which is the odd one out? (a) run fans in empty rooms (b) use old filament bulbs (c) iron one shirt at a time (d) switch off empty rooms
  33. 33.🧾 A family uses 130 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  34. 34.🧾 A family uses 190 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  35. 35.🧾 A family uses 190 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
  36. 36.🧾 A family uses 50 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  37. 37.🧾 A 50 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  38. 38.🧾 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?
  39. 39.True or false: to use LED lamps wastes electricity. (a) False (b) True
  40. 40.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?

Answer key

  1. an LED lamp
  2. False
  3. 1 kilowatt-hour (kWh)
  4. use old filament bulbs
  5. 720
  6. close the fridge quickly
  7. 189
  8. 140
  9. wastes electricity
  10. 4
  11. switch off empty rooms
  12. True
  13. 0.8
  14. True
  15. 567
  16. 150
  17. set the AC to 24 °C
  18. True
  19. False
  20. wastes electricity
  21. 153
  22. 680
  23. 255
  24. 340
  25. set the AC to 24 °C
  26. saves electricity
  27. 15
  28. 6
  29. False
  30. use daylight to read
  31. 360
  32. switch off empty rooms
  33. 910
  34. 1710
  35. 1140
  36. 400
  37. 0.2
  38. 85
  39. False
  40. 170

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