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Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 689 · 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 ampere (b) 1 volt (c) 1 watt (d) 1 kilowatt-hour (kWh)
  2. 2.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
  3. 3.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
  4. 4.Which of these wastes electricity? (a) close the fridge quickly (b) set the AC to 24 °C (c) unplug idle chargers (d) use old filament bulbs
  5. 5.True or false: to switch off empty rooms wastes electricity. (a) True (b) False
  6. 6.Which of these saves electricity? (a) run fans in empty rooms (b) use old filament bulbs (c) switch off empty rooms (d) iron one shirt at a time
  7. 7.🧾 A 2000 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  8. 8.Which of these saves electricity? (a) close the fridge quickly (b) iron one shirt at a time (c) use old filament bulbs (d) run fans in empty rooms
  9. 9.🧾 A 50 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  10. 10.🧾 A 100 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  11. 11.🔍 Which is the odd one out? (a) leave the TV on standby (b) run fans in empty rooms (c) use daylight to read (d) use old filament bulbs
  12. 12.True or false: to use daylight to read wastes electricity. (a) False (b) True
  13. 13.🧾 Which lamp gives the same light for the least power? (a) an oil lamp (b) a candle (c) an LED lamp (d) a filament bulb
  14. 14.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
  15. 15.True or false: to use LED lamps saves electricity. (a) False (b) True
  16. 16.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
  17. 17.🧾 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?
  18. 18.Which of these saves electricity? (a) unplug idle chargers (b) use old filament bulbs (c) leave the TV on standby (d) run fans in empty rooms
  19. 19.True or false: to use daylight to read saves electricity. (a) False (b) True
  20. 20.🧾 A family uses 200 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  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 6 hours. How many watt-hours (Wh) are saved?
  22. 22.Which of these wastes electricity? (a) set the AC to 24 °C (b) leave the TV on standby (c) close the fridge quickly (d) switch off empty rooms
  23. 23.🧾 A 200 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  24. 24.Which of these saves electricity? (a) run fans in empty rooms (b) set the AC to 24 °C (c) leave fridge door open (d) leave the TV on standby
  25. 25.🧾 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?
  26. 26.Which of these wastes electricity? (a) switch off empty rooms (b) run fans in empty rooms (c) use LED lamps (d) close the fridge quickly
  27. 27.True or false: to close the fridge quickly wastes electricity. (a) True (b) False
  28. 28.🧾 A family uses 20 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  29. 29.Which of these wastes electricity? (a) switch off empty rooms (b) iron one shirt at a time (c) use LED lamps (d) use daylight to read
  30. 30.🧾 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?
  31. 31.🧾 A family uses 140 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
  32. 32.🔍 Which is the odd one out? (a) switch off empty rooms (b) iron one shirt at a time (c) leave fridge door open (d) leave the TV on standby
  33. 33.True or false: to set the AC to 24 °C wastes electricity. (a) False (b) True
  34. 34.🧾 A 1000 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
  35. 35.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
  36. 36.Which of these saves electricity? (a) iron one shirt at a time (b) use old filament bulbs (c) run fans in empty rooms (d) use daylight to read
  37. 37.🧾 A 50 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
  38. 38.🧾 A family uses 100 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  39. 39.🧾 A 2000 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
  40. 40.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity

Answer key

  1. 1 kilowatt-hour (kWh)
  2. wastes electricity
  3. 1
  4. use old filament bulbs
  5. False
  6. switch off empty rooms
  7. 4
  8. close the fridge quickly
  9. 0.1
  10. 1
  11. use daylight to read
  12. False
  13. an LED lamp
  14. 850
  15. True
  16. saves electricity
  17. 255
  18. unplug idle chargers
  19. True
  20. 1400
  21. 306
  22. leave the TV on standby
  23. 2
  24. set the AC to 24 °C
  25. 51
  26. run fans in empty rooms
  27. False
  28. 160
  29. iron one shirt at a time
  30. 189
  31. 980
  32. switch off empty rooms
  33. False
  34. 5
  35. wastes electricity
  36. use daylight to read
  37. 0.4
  38. 800
  39. 20
  40. wastes electricity

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