Re: Crooke's Radiometer

[Gary Isenhower <garyi@bcm.tmc.edu>]

Bernard L Cohen wrote:

>         -I would bet that it was meant as a demonstration of radiation
> pressure, the fact that radiation has momentum, and sometime later
> somebody noticed that the rotation was in the wrong direction for that
> explanation.

I do remember a story included in my college physics text of just this
event.  There was a debate over the wave/particle nature of photons, and
some one (Einstein, I think) brought in a radiometer to show that they
must have momentum, and consequently mass.  
    _____________________________________________________________
	Just the humble opinion of,

	Gary Isenhower
        garyi@bcm.tmc.edu

"One of the illusions of life is that the present
hour is not the critical decisive hour. Write it
on you heart that every day is the best day of
the year."
                                - R. W. Emerson -
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