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Re: Transfering an Electrical Concept



At 10:51 AM -0600 12/17/00, brian whatcott, you wrote about
Transfering an Electrical Concept - matching mechanical:


The maximum power theorem is well known to electrical engineers.
It may be expressed like this:
Maximal power is transfered when the source impedance equals
the characteristic impedance of the output.


What is a reasonable explanation for the need to choose an optimal
bolt mass in a crossbow for best range?
Impulse? Change of momentum?

I had thought a bit along these lines several years ago when some
students were designing a trebouchet but did not finalize anything.

Using the analogy to the electrical case where P = IV , mechanics has
P = F x v (velocity)

Electrical impedance is V/I so I suggest that mechanical 'impedance'
is F / v = m (a/v).

I dunno if this has ANY validity, but since nobody else dove in, I
decided to speak up.

further comments would be MOST welcome.

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