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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 787 · 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.True or false: to use daylight to read wastes electricity. (a) True (b) False
  2. 2.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
  3. 3.Which of these saves electricity? (a) set the AC to 24 °C (b) leave the TV on standby (c) run fans in empty rooms (d) leave fridge door open
  4. 4.Which of these saves electricity? (a) use old filament bulbs (b) leave fridge door open (c) close the fridge quickly (d) leave the TV on standby
  5. 5.🧾 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?
  6. 6.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) an oil lamp (c) an LED lamp (d) a candle
  7. 7.Which of these saves electricity? (a) leave fridge door open (b) run fans in empty rooms (c) switch off empty rooms (d) leave the TV on standby
  8. 8.True or false: to use LED lamps wastes electricity. (a) True (b) False
  9. 9.True or false: to set the AC to 24 °C wastes electricity. (a) True (b) False
  10. 10.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) use LED lamps (c) close the fridge quickly (d) iron one shirt at a time
  11. 11.Which of these wastes electricity? (a) switch off empty rooms (b) use daylight to read (c) close the fridge quickly (d) use old filament bulbs
  12. 12.💡 Does it save or waste electricity to use old filament bulbs? (a) wastes electricity (b) saves electricity
  13. 13.Which of these wastes electricity? (a) leave fridge door open (b) unplug idle chargers (c) use LED lamps (d) use daylight to read
  14. 14.💡 Does it save or waste electricity to close the fridge quickly? (a) saves electricity (b) wastes electricity
  15. 15.True or false: to close the fridge quickly saves electricity. (a) False (b) True
  16. 16.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
  17. 17.🧾 A 50 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  18. 18.💡 Does it save or waste electricity to run fans in empty rooms? (a) saves electricity (b) wastes electricity
  19. 19.🔍 Which is the odd one out? (a) use old filament bulbs (b) switch off empty rooms (c) leave the TV on standby (d) leave fridge door open
  20. 20.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 ampere (c) 1 kilowatt-hour (kWh) (d) 1 volt
  21. 21.🧾 A family uses 40 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  22. 22.True or false: to use daylight to read saves electricity. (a) True (b) False
  23. 23.🧾 A 1000 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  24. 24.🧾 A family uses 150 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  25. 25.🧾 A 250 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  26. 26.🧾 A family uses 60 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  27. 27.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
  28. 28.🔍 Which is the odd one out? (a) use old filament bulbs (b) use LED lamps (c) leave the TV on standby (d) run fans in empty rooms
  29. 29.🔍 Which is the odd one out? (a) leave fridge door open (b) use old filament bulbs (c) run fans in empty rooms (d) unplug idle chargers
  30. 30.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 9 hours. How many watt-hours (Wh) are saved?
  31. 31.Which of these wastes electricity? (a) close the fridge quickly (b) switch off empty rooms (c) run fans in empty rooms (d) use LED lamps
  32. 32.🔍 Which is the odd one out? (a) unplug idle chargers (b) set the AC to 24 °C (c) use LED lamps (d) leave the TV on standby
  33. 33.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
  34. 34.True or false: to iron one shirt at a time saves electricity. (a) True (b) False
  35. 35.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
  36. 36.True or false: to close the fridge quickly wastes electricity. (a) False (b) True
  37. 37.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 5 hours. How many watt-hours (Wh) are saved?
  38. 38.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  39. 39.🧾 A 2000 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  40. 40.True or false: to use old filament bulbs saves electricity. (a) True (b) False

Answer key

  1. False
  2. saves electricity
  3. set the AC to 24 °C
  4. close the fridge quickly
  5. 170
  6. an LED lamp
  7. switch off empty rooms
  8. False
  9. False
  10. iron one shirt at a time
  11. use old filament bulbs
  12. wastes electricity
  13. leave fridge door open
  14. saves electricity
  15. True
  16. saves electricity
  17. 0.25
  18. wastes electricity
  19. switch off empty rooms
  20. 1 kilowatt-hour (kWh)
  21. 200
  22. True
  23. 2
  24. 600
  25. 0.5
  26. 480
  27. saves electricity
  28. use LED lamps
  29. unplug idle chargers
  30. 765
  31. run fans in empty rooms
  32. leave the TV on standby
  33. saves electricity
  34. False
  35. saves electricity
  36. False
  37. 170
  38. 1
  39. 16
  40. False

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