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Dave Plowman (News) Dave Plowman (News) is offline
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Default The physics of cars - a question sequence.

In article ,
michael adams wrote:

"Dave Plowman (News)" wrote in message
...
In article ,
michael adams wrote:
If the engine is running at maximum power, and thus the crankshaft
is turning as fast as possible, then how is it possible for less than
maximum torque to be delivered to the flywheel ?


I'm beginning to lose the will to live.

Power is a function of torque and engine speed. It therefore goes
without saying that maximum power will always be delivered at higher
revs than maximum torque in practice.


That may well go without saying for you, but it isn't intuitively
obvious to me.


It is simple maths. If BHP is a function of RPM and torque, and the torque
remains constant, then higher RPM means higher BHP.

It may have said something similar on some website, complete with
diagrams and coloured lines, so I'm not going to tear my hair
out over it, either way.


If you looked at graphs showing an engine's output relative to RPM, you'd
see two plots, one for BHP and the other for torque. Often shown in the
same graph. Both will rise and then fall as RPM increases. The torque one
will have its peak at lower RPM than the BHP.

It's something I've known since a child. ;-)

--
*The severity of the itch is proportional to the reach *

Dave Plowman London SW
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