Electronics Worksheet: Electricity Units

Electronics lesson 19: Electricity units and saving power · Set 279 · 40 questions

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.

1. 1.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
2. 2.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
3. 3.🧾 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?
4. 4.Which of these wastes electricity? (a) use LED lamps (b) close the fridge quickly (c) use daylight to read (d) leave fridge door open
5. 5.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
6. 6.🧾 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?
7. 7.🧾 A 50 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
8. 8.🧾 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
9. 9.🔍 Which is the odd one out? (a) run fans in empty rooms (b) leave fridge door open (c) switch off empty rooms (d) iron one shirt at a time
10. 10.True or false: to run fans in empty rooms saves electricity. (a) True (b) False
11. 11.True or false: to use daylight to read saves electricity. (a) True (b) False
12. 12.🔍 Which is the odd one out? (a) iron one shirt at a time (b) run fans in empty rooms (c) close the fridge quickly (d) leave the TV on standby
13. 13.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 volt (c) 1 ampere (d) 1 watt
14. 14.💡 Does it save or waste electricity to leave fridge door open? (a) wastes electricity (b) saves electricity
15. 15.🧾 A family uses 40 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
16. 16.Which of these saves electricity? (a) leave the TV on standby (b) run fans in empty rooms (c) switch off empty rooms (d) leave fridge door open
17. 17.🧾 A 1500 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
18. 18.🧾 A 250 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
19. 19.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
20. 20.True or false: to use LED lamps wastes electricity. (a) False (b) True
21. 21.Which of these saves electricity? (a) leave the TV on standby (b) use daylight to read (c) iron one shirt at a time (d) run fans in empty rooms
22. 22.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
23. 23.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
24. 24.Which of these saves electricity? (a) iron one shirt at a time (b) use old filament bulbs (c) leave the TV on standby (d) close the fridge quickly
25. 25.🧾 A family uses 30 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
26. 26.🔍 Which is the odd one out? (a) iron one shirt at a time (b) use old filament bulbs (c) unplug idle chargers (d) leave the TV on standby
27. 27.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) switch off empty rooms (c) use old filament bulbs (d) use daylight to read
28. 28.Which of these saves electricity? (a) run fans in empty rooms (b) leave fridge door open (c) leave the TV on standby (d) set the AC to 24 °C
29. 29.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) leave the TV on standby (c) unplug idle chargers (d) use daylight to read
30. 30.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
31. 31.Which of these saves electricity? (a) leave the TV on standby (b) unplug idle chargers (c) run fans in empty rooms (d) leave fridge door open
32. 32.Which of these wastes electricity? (a) run fans in empty rooms (b) use LED lamps (c) set the AC to 24 °C (d) switch off empty rooms
33. 33.🧾 A 100 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
34. 34.True or false: to use old filament bulbs saves electricity. (a) True (b) False
35. 35.🧾 A family uses 130 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
36. 36.🧾 A family uses 170 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
37. 37.🔍 Which is the odd one out? (a) use LED lamps (b) unplug idle chargers (c) set the AC to 24 °C (d) run fans in empty rooms
38. 38.🧾 A 250 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
39. 39.True or false: to use daylight to read wastes electricity. (a) True (b) False
40. 40.True or false: to run fans in empty rooms wastes electricity. (a) True (b) False

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