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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 235 · 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.💡 Does it save or waste electricity to use old filament bulbs? (a) wastes electricity (b) saves electricity
  2. 2.🔍 Which is the odd one out? (a) use LED lamps (b) use daylight to read (c) leave fridge door open (d) unplug idle chargers
  3. 3.Which of these wastes electricity? (a) set the AC to 24 °C (b) run fans in empty rooms (c) switch off empty rooms (d) use daylight to read
  4. 4.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  5. 5.Which of these wastes electricity? (a) close the fridge quickly (b) switch off empty rooms (c) set the AC to 24 °C (d) use old filament bulbs
  6. 6.🧾 A family uses 110 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
  7. 7.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
  8. 8.True or false: to run fans in empty rooms saves electricity. (a) False (b) True
  9. 9.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  10. 10.🧾 A 50 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
  11. 11.🧾 A family uses 80 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  12. 12.🧾 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?
  13. 13.🧾 A 1500 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  14. 14.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) an oil lamp (c) a candle (d) an LED lamp
  15. 15.Which of these wastes electricity? (a) iron one shirt at a time (b) use daylight to read (c) set the AC to 24 °C (d) switch off empty rooms
  16. 16.💡 Does it save or waste electricity to iron one shirt at a time? (a) saves electricity (b) wastes electricity
  17. 17.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) use old filament bulbs (c) leave the TV on standby (d) leave fridge door open
  18. 18.Which of these saves electricity? (a) use LED lamps (b) leave fridge door open (c) use old filament bulbs (d) iron one shirt at a time
  19. 19.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  20. 20.🧾 A family uses 40 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
  21. 21.🔍 Which is the odd one out? (a) iron one shirt at a time (b) close the fridge quickly (c) use daylight to read (d) unplug idle chargers
  22. 22.🔍 Which is the odd one out? (a) leave fridge door open (b) leave the TV on standby (c) use old filament bulbs (d) use daylight to read
  23. 23.💡 Does it save or waste electricity to run fans in empty rooms? (a) saves electricity (b) wastes electricity
  24. 24.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 kilowatt-hour (kWh) (c) 1 watt (d) 1 ampere
  25. 25.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
  26. 26.True or false: to switch off empty rooms saves electricity. (a) False (b) True
  27. 27.True or false: to switch off empty rooms wastes electricity. (a) True (b) False
  28. 28.True or false: to iron one shirt at a time saves electricity. (a) True (b) False
  29. 29.🔍 Which is the odd one out? (a) close the fridge quickly (b) set the AC to 24 °C (c) use old filament bulbs (d) use LED lamps
  30. 30.True or false: to close the fridge quickly saves electricity. (a) True (b) False
  31. 31.🔍 Which is the odd one out? (a) switch off empty rooms (b) use old filament bulbs (c) run fans in empty rooms (d) iron one shirt at a time
  32. 32.🧾 A family uses 150 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  33. 33.🧾 A family uses 30 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
  34. 34.🧾 A 250 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  35. 35.🧾 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?
  36. 36.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
  37. 37.Which of these saves electricity? (a) leave fridge door open (b) close the fridge quickly (c) leave the TV on standby (d) use old filament bulbs
  38. 38.True or false: to use LED lamps wastes electricity. (a) False (b) True
  39. 39.🔍 Which is the odd one out? (a) leave fridge door open (b) iron one shirt at a time (c) use old filament bulbs (d) close the fridge quickly
  40. 40.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity

Answer key

  1. wastes electricity
  2. leave fridge door open
  3. run fans in empty rooms
  4. 0.4
  5. use old filament bulbs
  6. 550
  7. wastes electricity
  8. False
  9. saves electricity
  10. 0.3
  11. 720
  12. 170
  13. 7.5
  14. an LED lamp
  15. iron one shirt at a time
  16. wastes electricity
  17. set the AC to 24 °C
  18. use LED lamps
  19. 1
  20. 240
  21. iron one shirt at a time
  22. use daylight to read
  23. wastes electricity
  24. 1 kilowatt-hour (kWh)
  25. wastes electricity
  26. True
  27. False
  28. False
  29. use old filament bulbs
  30. True
  31. switch off empty rooms
  32. 600
  33. 180
  34. 0.5
  35. 63
  36. saves electricity
  37. close the fridge quickly
  38. False
  39. close the fridge quickly
  40. saves electricity

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