>> (Also curios is the fact that the car doesn't accelerate when you 
>> drive it down a hill... You'd think it would.)
> 
> Press the clutch and start off at 5mph so as to avoid any air drag.  It 
> should accelerate then.

Oh, it *does* accelerate... just... not very much. I mean, if you point 
a *bicycle* downhill, it takes off like a rocket. And it doesn't even 
weigh much! But a much heaveir car... doesn't seem to pick up speed very 
much.

>> I would think this electric motor trickery probably also saves fuel on 
>> low-speed manovers like trying to park. [Think how much you have to 
>> rev the engine to make a car move that slowly...]
> 
> Ermm, my car moves just by lifting the clutch gently, no need to rev at 
> all.

Is your car diesel by any chance?

>> ...OK, so maybe it wasn't exactly 10^(-6). But it worked out to be 
>> some absurdly small figure anyway.
> 
> IIRC you meant that amount per revolution of the engine, not per minute!

Right. So given that there's roughly 10^3 revolutions per minute, that 
would be about 10^(-3) L per minute. ;-)

>> I've always wanted to know... An engine is a mechanical device. So why 
>> does temperature have any effect on anything?
> 
> Things expand with temperature, an engine is designed to run smoothly at 
> it's operating temperature, below that there is a lot more friction.

Ah, I see. That would make sense...



-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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