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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 823 · 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.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 watt (c) 1 kilowatt-hour (kWh) (d) 1 ampere
  2. 2.🧾 A family uses 30 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  3. 3.🧾 A family uses 50 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  4. 4.🔍 Which is the odd one out? (a) run fans in empty rooms (b) use old filament bulbs (c) leave the TV on standby (d) use daylight to read
  5. 5.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
  6. 6.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
  7. 7.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
  8. 8.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) switch off empty rooms (c) iron one shirt at a time (d) use daylight to read
  9. 9.Which of these wastes electricity? (a) use daylight to read (b) set the AC to 24 °C (c) leave the TV on standby (d) unplug idle chargers
  10. 10.Which of these wastes electricity? (a) set the AC to 24 °C (b) close the fridge quickly (c) unplug idle chargers (d) run fans in empty rooms
  11. 11.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave fridge door open (c) use old filament bulbs (d) set the AC to 24 °C
  12. 12.🧾 A family uses 200 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  13. 13.🔍 Which is the odd one out? (a) run fans in empty rooms (b) switch off empty rooms (c) close the fridge quickly (d) use daylight to read
  14. 14.Which of these wastes electricity? (a) switch off empty rooms (b) unplug idle chargers (c) use old filament bulbs (d) close the fridge quickly
  15. 15.True or false: to iron one shirt at a time wastes electricity. (a) True (b) False
  16. 16.🧾 Which lamp gives the same light for the least power? (a) an LED lamp (b) a filament bulb (c) an oil lamp (d) a candle
  17. 17.True or false: to use daylight to read wastes electricity. (a) True (b) False
  18. 18.Which of these saves electricity? (a) leave the TV on standby (b) set the AC to 24 °C (c) use old filament bulbs (d) leave fridge door open
  19. 19.🔍 Which is the odd one out? (a) use LED lamps (b) unplug idle chargers (c) set the AC to 24 °C (d) leave fridge door open
  20. 20.True or false: to run fans in empty rooms saves electricity. (a) True (b) False
  21. 21.🧾 A family uses 140 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  22. 22.Which of these saves electricity? (a) use old filament bulbs (b) run fans in empty rooms (c) leave the TV on standby (d) unplug idle chargers
  23. 23.True or false: to close the fridge quickly wastes electricity. (a) True (b) False
  24. 24.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  25. 25.🧾 A 1000 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  26. 26.🧾 A family uses 20 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  27. 27.True or false: to set the AC to 24 °C saves electricity. (a) True (b) False
  28. 28.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 4 hours. How many watt-hours (Wh) are saved?
  29. 29.Which of these wastes electricity? (a) switch off empty rooms (b) use LED lamps (c) use daylight to read (d) iron one shirt at a time
  30. 30.Which of these saves electricity? (a) leave the TV on standby (b) run fans in empty rooms (c) use daylight to read (d) leave fridge door open
  31. 31.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
  32. 32.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
  33. 33.True or false: to leave fridge door open wastes electricity. (a) False (b) True
  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 run fans in empty rooms? (a) saves electricity (b) wastes electricity
  36. 36.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  37. 37.💡 Does it save or waste electricity to use LED lamps? (a) saves electricity (b) wastes electricity
  38. 38.True or false: to use old filament bulbs wastes electricity. (a) True (b) False
  39. 39.True or false: to unplug idle chargers 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 6 hours. How many watt-hours (Wh) are saved?

Answer key

  1. 1 kilowatt-hour (kWh)
  2. 120
  3. 450
  4. use daylight to read
  5. saves electricity
  6. saves electricity
  7. saves electricity
  8. iron one shirt at a time
  9. leave the TV on standby
  10. run fans in empty rooms
  11. set the AC to 24 °C
  12. 1400
  13. run fans in empty rooms
  14. use old filament bulbs
  15. True
  16. an LED lamp
  17. False
  18. set the AC to 24 °C
  19. leave fridge door open
  20. False
  21. 560
  22. unplug idle chargers
  23. False
  24. 0.4
  25. 4
  26. 80
  27. True
  28. 340
  29. iron one shirt at a time
  30. use daylight to read
  31. wastes electricity
  32. saves electricity
  33. True
  34. False
  35. wastes electricity
  36. saves electricity
  37. saves electricity
  38. True
  39. False
  40. 510

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