ELECTRICITYELECTRICITY

PhysicsPhysics

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Electrical PowerElectrical PowerUnit of electricityUnit of electricityKilowatt-hour meterKilowatt-hour meterMain CircuitMain Circuit

Electrical PowerElectrical Power

Power = Energy change / timeunit of power: Watt (W)unit of energy: Joule (J) unit of time: second (s)1W = 1Js-1

Unit of ElectricityUnit of Electricity

- - The energy consumed in household appliances The energy consumed in household appliances is measured in is measured in kilowatt-hours (kWh)kilowatt-hours (kWh)

- - One kilowatt-hour is the amount of energy One kilowatt-hour is the amount of energy that is used by a 1000 W appliance in one hour. that is used by a 1000 W appliance in one hour.

Appliance Rating/W Operating Energy used Cost per time per day per day day/$

Clock 5 24TV 40 7Karaoke 200 2Heater 1500 8Total per day Total in June

The total cost of electricity consumption in June

0.120.280.412

0.0840.1960.288.4

12.8384

8.96268.8

Electricity BillElectricity Bill

Chan Tai Man13 Nathan RoadKowloon

85467-253-07

Chan Tai Man13 Nathan RoadKowloon

28-04-98共 日用電量

由 至59

01-03-98 28-04-98

06-05-98

Kilowatt-hour meterWhen the mains cable enters the home, it is connected through a fuse to a kilowatt-hour meter.

http://www.hec.com.hk

Hong Kong Electric Holdings Ltd.

China Light & Power Co. Ltd.

http://www.clphk.com.hk

Two Electrical Suppliers in Hong Kong: