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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 614 · 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 of these wastes electricity? (a) unplug idle chargers (b) use LED lamps (c) close the fridge quickly (d) iron one shirt at a time
  2. 2.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
  3. 3.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 volt (c) 1 kilowatt-hour (kWh) (d) 1 watt
  4. 4.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
  5. 5.🔍 Which is the odd one out? (a) use daylight to read (b) set the AC to 24 °C (c) leave the TV on standby (d) unplug idle chargers
  6. 6.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  7. 7.True or false: to use daylight to read wastes electricity. (a) True (b) False
  8. 8.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
  9. 9.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) use daylight to read (c) switch off empty rooms (d) use old filament bulbs
  10. 10.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
  11. 11.🔍 Which is the odd one out? (a) leave fridge door open (b) iron one shirt at a time (c) leave the TV on standby (d) use daylight to read
  12. 12.🧾 A family uses 70 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  13. 13.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave fridge door open (c) run fans in empty rooms (d) set the AC to 24 °C
  14. 14.Which of these saves electricity? (a) use LED lamps (b) leave the TV on standby (c) run fans in empty rooms (d) iron one shirt at a time
  15. 15.Which of these wastes electricity? (a) switch off empty rooms (b) unplug idle chargers (c) run fans in empty rooms (d) use LED lamps
  16. 16.💡 Does it save or waste electricity to use LED lamps? (a) wastes electricity (b) saves electricity
  17. 17.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
  18. 18.🧾 A 2000 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  19. 19.🧾 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?
  20. 20.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 5 hours. How many watt-hours (Wh) are saved?
  21. 21.🧾 Which lamp gives the same light for the least power? (a) an oil lamp (b) an LED lamp (c) a candle (d) a filament bulb
  22. 22.🔍 Which is the odd one out? (a) iron one shirt at a time (b) use daylight to read (c) set the AC to 24 °C (d) close the fridge quickly
  23. 23.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
  24. 24.🔍 Which is the odd one out? (a) leave the TV on standby (b) iron one shirt at a time (c) close the fridge quickly (d) leave fridge door open
  25. 25.True or false: to iron one shirt at a time saves electricity. (a) False (b) True
  26. 26.🧾 A family uses 50 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
  27. 27.🔍 Which is the odd one out? (a) use LED lamps (b) run fans in empty rooms (c) close the fridge quickly (d) unplug idle chargers
  28. 28.🧾 A 50 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  29. 29.🧾 A 50 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  30. 30.True or false: to run fans in empty rooms wastes electricity. (a) False (b) True
  31. 31.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
  32. 32.🧾 A family uses 170 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  33. 33.True or false: to switch off empty rooms saves electricity. (a) True (b) False
  34. 34.🧾 A 200 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  35. 35.True or false: to close the fridge quickly saves electricity. (a) True (b) False
  36. 36.🧾 A family uses 150 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
  37. 37.True or false: to run fans in empty rooms saves electricity. (a) False (b) True
  38. 38.🧾 A 200 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  39. 39.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
  40. 40.True or false: to leave fridge door open saves electricity. (a) False (b) True

Answer key

  1. iron one shirt at a time
  2. saves electricity
  3. 1 kilowatt-hour (kWh)
  4. wastes electricity
  5. leave the TV on standby
  6. saves electricity
  7. False
  8. leave the TV on standby
  9. use old filament bulbs
  10. 51
  11. use daylight to read
  12. 560
  13. set the AC to 24 °C
  14. use LED lamps
  15. run fans in empty rooms
  16. saves electricity
  17. 68
  18. 8
  19. 85
  20. 255
  21. an LED lamp
  22. iron one shirt at a time
  23. wastes electricity
  24. close the fridge quickly
  25. False
  26. 450
  27. run fans in empty rooms
  28. 0.5
  29. 0.2
  30. True
  31. saves electricity
  32. 1190
  33. True
  34. 1
  35. True
  36. 600
  37. False
  38. 2
  39. saves electricity
  40. False

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