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→Energy Usage of Appliances
: The amount of [[energy]] an '''appliance''' uses depends on the power rating and how long the '''appliance''' is used for.
: [[Energy]] usage for '''appliances''' is measured in [[kilowatt-hour]]s.
{| class="wikitable"
|+ The Power ratings of some electrical appliances.
|-
| style="height:20px; width:200px; text-align:center;" |Filament Bulb
A 60[[Watt]] filament bulb may be used for 8 hours a day. Calculate the [[energy]] in kilowatt-hours.
| style="height:20px; width:200px; text-align:center;" |Energy Saving Bulb
A 25[[Watt]] energy saving bulb may be used for 8 hours a day. Calculate the [[energy]] in kilowatt-hours.
| style="height:20px; width:200px; text-align:center;" |Kettle
A 2000[[Watt]] kettle may be used for 30 minutes a day. Calculate the [[energy]] in kilowatt-hours.
|-
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 60W = 0.060kW
Time = 8 hours
Energy = 0.060 x 8
Energy = 0.48kilowatt-hours
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 25W = 0.025kW
Time = 8 hours
Energy = 0.025 x 8
Energy = 0.20kilowatt-hours
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 2000W = 2.0kW
Time = 30 minutes = 0.5hours
Energy = 2.0 x 0.5
Energy = 1.0kilowatt-hours
|-
| style="height:20px; width:200px; text-align:center;" |Television
A 250[[Watt]] television is left on for 3 hours each day.
| style="height:20px; width:200px; text-align:center;" |Refrigerator
A 200[[Watt]] refrigerator is on for 24 hours each day.
| style="height:20px; width:200px; text-align:center;" |Oven
A 2500[[Watt]] television is left on for 45 minutes each day.
|-
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 250W = 0.25kW
Time = 3 hours
Energy = 0.25 x 3
Energy = 0.75kilowatt-hours
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 200W = 0.20kW
Time = 24 hours
Energy = 0.20 x 24
Energy = 4.8kilowatt-hours
| style="height:20px; width:200px; text-align:center;" |
Energy = Power x time
Power = 2500W = 2.5kW
Time = 45 minutes = 0.75 hours
Energy = 2.5 x 0.75
Energy = 1.875kilowatt-hours
|}