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Re: mass versus radiation resistance



At 09:40 PM 4/8/01 -0400, Robert B Zannelli wrote:
I understand that by making the time required to attain a specific
velocity arbitrarily long we reduce the specific radiation resistance to a
very small value.

OK.

However this very small value would be averaged over a much longer time.

The radiation power goes like acceleration *squared*. To get the energy,
we multiply this small-squared quantity by a long time, and we still get a
small energy.

Doesn't radiation resistance "store" energy of motion in a similar way
that inertia does for particles in motion.

No.

The kinetic energy depends only on the final velocity, not how long it took
to reach that final velocity. In contrast, total energy lost to radiation
resistance can be made arbitrarily small by using small accelerations.

=================

Understanding the difference between dissipated energy and stored energy
has technological applications:

This crops up in the analysis of "adiabatic logic" circuits. The I^2 R
power dissipated in the resistances goes down like the clock rate *squared*
so the energy dissipated per operation goes down like the clock rate, when
it is slow compared to 1/RC. Meanwhile the energy transferred remains .5 C
V^2 independent of clock rate.

Standard famous textbooks say this can't be done. They say that you must
dissipate .5 C V^2 per operation. But you don't. For details you can go to
http://www.uspto.gov/
and ask for patent numbers
5,473,270 5,477,164 5,506,519 5,559,463