Electricity

[Sigmarus]

Electricity

-What is the clearest way of differing kW(Kilo-watt) and kWh(Kilo-watt/hour)?I get confused sometimes.

 

Thanks

[studiot]

Electricity

-What is the clearest way of differing kW(Kilo-watt) and kWh(Kilo-watt/hour)?I get confused sometimes.

 

Thanks

 

Before I answer this please tell me what you think a 'watt' is because a kilowatt is one thousand of them.

[Sigmarus]

Amount of work done by an electric current per unit time

[J.C.MacSwell]

Electricity

-What is the clearest way of differing kW(Kilo-watt) and kWh(Kilo-watt/hour)?I get confused sometimes.

 

Thanks

kWh isn't kW/hour. It is kW (power) for (not per) an hour (time), giving you energy.

[studiot]

Amount of work done by an electric current per unit time

 

Sounds good.

 

How about the amount of heat generated per unit time?

 

So work or heat per unit time.

 

And what is the unit of work or heat?

 

Well it is the Joule, since both are forms of energy.

 

and what is the unit of time?

 

The second.

 

So 1 watt is one joule per second.

 

But watts are not energy, we must not forget the per unit time or per second part.

 

Watts are the units of Power which is the time rate of doing work or producing heat.

 

 

 

So to remember time how many seconds in one hour?

 

3600

 

 

So if we are working or producing heat at a rate of 1 joule per second we will have produced 1 x 3600 joules in 1 hour.

 

This amount of energy is called the watt-hour.

 

Of course if we multiply everything by 1000 we get

 

So if we are working or producing heat at a rate of 1000 joules per second we will have produced 1000 x 3600 joules in 1 hour.

 

Or to use the kilo prefix

 

 

So if we are working or producing heat at a rate of 1 kilojoule per second we will have produced 1 x 3600 kilojoules in 1 hour.

 

This is called a kilowatt-hour.