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Miketmbt
2008-May-21, 05:51 PM
Hello,

I have something bothering me. Im hoping all you brilliant people could shed some light on this and make me feel dumb:doh:

First, are my facts straight? (I rounded speed of light up to 300,000 kms)

If I am traveling at near the speed of light and I turn on a flashlight, the light will leave leave my flashlight at 300,000 km/s even though I am traveling at 99.9999999% of that?

Questions
Would that not initally project my light faster than the light speed barrier?

X is traveling through space at 299,000 km/s.
Y leaves X at 299,000 km/s.

Nevermind. Now that I wrote it down, my thoughts dont really make any sense.:wall:

NEOWatcher
2008-May-21, 06:06 PM
Would that not initally project my light faster than the light speed barrier?
Initially? Do you see something as being variable? I'm not sure why you would phrase it this way.


X is traveling through space at 299,000 km/s.
Y leaves X at 299,000 km/s.

Who is watching who?
If Y leaves X at that speed it implies that it's in relation to X. To an outside observer, Y is only going marginally faster than X.

Bozola
2008-May-21, 06:14 PM
Yup. Your "local" second isn't the same duration as an external observer's "local" second.

Miketmbt
2008-May-21, 06:17 PM
Who is watching who?
If Y leaves X at that speed it implies that it's in relation to X. To an outside observer, Y is only going marginally faster than X.

Ok. I need to add Z then.

X is watching Y. Z is watching X and Y.



Initially? Do you see something as being variable? I'm not sure why you would phrase it this way.

Yeah, I guess "initally" is a bad word for a constant. I just imagined a projection into a rapid deceleration for no good reason.

NEOWatcher
2008-May-21, 07:11 PM
Ok. I need to add Z then.
X is watching Y. Z is watching X and Y.

Right, distance viewed from X is not the same as viewed from Z.
X thinks she's standing still and Z is moving.
Z thinks he/she is standing still and X is moving.
They both see Y as traveling at light speed.