On Tue, 16 Sep 2008 17:19:14 -0700, Richard Clark
wrote:

On Tue, 16 Sep 2008 16:47:54 -0700 (PDT), Art Unwin
wrote:

On Sep 16, 4:32*pm, Cecil Moore wrote:
Photons have zero rest mass.
a photon at rest, how droll.
Cecil, this sounds like a regular poster David.Perhaps he is pulling
your leg with his nonsence

We know that we can accelerate an electron to 90% of the speed of
light - it happens every femtosecond in one of any 100 billion crt
displays still glowing in the world. Some of us know its mass at this
speed. A question for the Newtonian philosopherz:
"What is the mass of a photon traveling at 90% of the speed of
light?"

Ah, yes!

No Newtonians in this crowd. Perhaps it was the relativistic term
"speed of light" that confused this group so much. Let's restate it
in units that Newton could have appreciated.

We know that we can accelerate an electron to 167,770 miles/s - it
happens every femtosecond in one of any 100 billion crt
displays still glowing in the world. Some of us know its mass at this
speed. A question for the Newtonian philosopherz:
"What is the mass of a photon traveling at 167,770 miles/s?"

73's
Richard Clark, KB7QHC