In article ,
Rob wrote:
Jim Lesurf wrote:
[snip]

I think if forced, under considerable duress and on pain of death, you
could (on a good day) guess what was meant :-)

Are you unclear on the distinction between 'energy' and 'power'? If so,
then the units used may well confuse.

Am I allowed to say Wh - would that be ambiguous?

For what? :-)

If you mean 'Wh' to mean 'Watt-hour' then this is a unit of energy. It
represents the energy conveyed/used if you consume power at the rate of 1
Watt, for a duration of 1 hour.

So if you have a light bulb rated at '100W' it will use up 1 kWh if you
leave it on for 10 hours. You then pay for energy (numbered in an amount of
kWh). A 50W light would have to be on for 20 hourse to use up 1kWh of
energy.

Also, imagine you have two immersion heaters. One 1 kW, the other 2 kW.

With perfect insulation, the 2kW heater will heat up a tank of water in
half the time that the 1kW heater will require to get the same rise in
temperature. But the amount of energy used will be the same whichever you
used. (In the real world, the insulation won't be perfect, so it won't be
that simple. However physicists are allowed to do things like ignore all
such annoying complications when trying to explain something. :-) )

Slainte,

Jim

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