On Thu, 21 Apr 2011, Capt. Deltic wrote:

On 21 Apr, 09:58, wrote:
On Thu, 21 Apr 2011 09:33:41 +0100

Graeme Wall wrote:
Pedantically they have motors, not engines. *The latter being those
nasty infernal combustion thingies. *Motors run on nice clean electrickery.

Tell that to Arthur Daley!

To be even more pedantic, an engine generates power, while a motor
consumes power.

What? *What*?

'Generates' power? 'Consumes' power? Has that small matter called the
first law of thermodynamics passed you by?

All any of these devices do is convert energy from one form to another.
They might be coupled to devices capable of storing energy. But whenever
they are in operation, the flows of energy in and out are equal; not all
of the energy coming out will be useful, but it's there. A flow of energy
is power, and so all these devices do is convert power from one form to
another.

An electric motor converts electrical power to mechanical power. An
internal combustion engine converts chemical power - a flow of constant
mass in which the output has a lower chemical potential than the input -
into mechanical power. An external combustion engine - if you were
inclined to exclude the boiler - converts pressure power (which can't be
the right name - aerostatic power?) into mechanical power. They're all
just power converters.

Calling one an engine and one a motor is a matter of convention. It's
preposterous to ascribe a fundamental meaning to the distinction.

tom

--
Eight-bit is forever