"toad" wrote in message
ps.com...
On 15 Oct, 14:27, (Richard Casady) wrote:

Why wouldn't it accellerate indefinitely with no friction anywhere in
the system.

....because as it approaches the speed of light it will require
infinate energy.


My flashlight shoots out photons at the speed of light and it is powered by
a 1 1/2 volt battery. Even better, my flashlight moves away from the photons
at the speed of light with the same 1 1/2 volt battery. When do I need to
change the battery?