traveling at about light speed and then turning on flash light - what's observed from outside?

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hypothetical. someone is traveling at almost the speed of light. they then turn on a flash light. i understand that how all observers to this will see the light move at a constant, the speed of light. that's based on relativity and frames of reference. 

what i dont understand, if an observer sees someone almost going at the speed of light, wouldn't the light have to appear to be going faster than light speed given the person moving and the light being emitted are in fact moving at different speeds? 

is it possible to appear to be moving at faster than light speed even if that's not in fact true? 
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@n8nrgmi

This is very similar to the thought experiment Einstein proposed to himself in his youth, which ultimately led him to developing special relativity.
The answer is that material objects cannot reach the speed of light, though they can get arbitrarily close to it. At any such speed, if you turn on the headlights of the spaceship, the light flies away, ahead of the ship, at the standard speed of light, both as measured by people on the ship and as measured by people on the ground.
Yes, that’s very strange. It means that measures of distances and times have to be different for the two groups of people, which is what special relativity predicts and what experiment verifies.
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@FLRW
i understand that light is traveling at the speed of light for all reference frames... but given the person moving is also going at almost the speed of light, how can the observer note both him and the light going at different speeds given the person is also going at almost the speed of light? is the person appearing to move slower than he is, or is the light appearing to move faster than it is? id think it'd have to be one or the other. i guess since i accept that light is constant in all reference frames, that the person must appear to moving much slower than he is. but i dont understand how that's possible given the person moving is almost going at the speed of light. 
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Special Relativity simplified using no math. Einstein thought experiments
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@FLRW
that didn't really answer my last post. but it did point out that things that are moving age slower. and i think it said that moving objects appear to move slower to the observer than they are actually moving. so maybe we can say that the person moving at almost the speed of light must appear to be moving slower even though he's moving at around the speed of light. there's still a tension there that doesn't make sense, how can two things moving around the speed of light appear to be moving at different speeds? but maybe that tension is the point of it all. i dont know.. i'm not saying i found a flaw in einsten's work, i'm just pointing out that there aren't many good explanations out there.
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Light speed us relative to the observer. This is counterintuitive but true. 
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hypothetical. someone is traveling at almost the speed of light. they then turn on a flash light. i understand that how all observers to this will see the light move at a constant, the speed of light. that's based on relativity and frames of reference. 

what i dont understand, if an observer sees someone almost going at the speed of light, wouldn't the light have to appear to be going faster than light speed given the person moving and the light being emitted are in fact moving at different speeds? 

is it possible to appear to be moving at faster than light speed even if that's not in fact true? 

Imagine you have a ship  [S] that is traveling at half the speed of light that sends out a beam of light ——->

On the ship after 1 second you see this:
 <—————-> (1ls)

[S]—————>

So the light has travelled 1 light second away from the ship.

If you’re on the ground watching the ship. In 1 second, you see this:

<——————->
            [S]———>

You see the ship has moved 1/2 a light second, and the light has only travelled 1/2 a light second away from the ship. (The light has travelled 1 light second total)

That’s so weird? How can the speed of light travel the same distance away from observers 1ls?

Imagine the ship has a huge clock on the side, and you have your own clock on the ground what would you see on the clocks..

<——————->
            [S]———> 
            0.5S

Ground clock: 1s

<——————-><——————->
                            [S]——————>
                            1s

Ground clock: 2s

The ships clock ticks slower so that when the clock has ticked to 1 second you will see the light 1light second away from the ship, even then the light has travelled 2 light seconds from your perspective, and take 2s to reach there.


Imagine if the ship is travelling even faster. 
<——————-><——————->
                                                 [S]—>
                                                  0.2s

In this case the ship has travelled almost 2 light second, the light is only a tiny amount in front of the ship: but according to the ships clock, only a fraction of a second has passed.



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The whole framework of Special Relativity is based on two fundamental postulates:
1. The laws of physics are the same in all inertial reference frames
2. The speed of light in vacuum is the same in all inertial reference frames.
To make more sense of this, let's review quickly what Special Relativity establishes. Special Relativity tells us that a moving frame of reference has its spatial dimension shortened in the direction of motion relative to the stationary observer, and has its time dimension slowed down relative to the stationary observer. These effects are known respectively as "length contraction" and "time dilation". Here on earth, we don't notice these effects in everyday life because we are going far too slowly. Length contraction and time dilation only become significant when you are traveling close to the speed of light. The speed of light is very fast (300,000 km/s or 670,000,000 mph), far faster than any speed that a typical human experiences relative to the stationary observer. Note that the key phrase is "relative to the stationary observer". Relative to itself, a reference frame is at rest and experiences neither length contraction nor time dilation. An astronaut on a speeding spaceship does not see his own rulers shortened nor his own clocks running slow. Rather, it is the man on the ground who sees the rulers on the spaceship shortened and the spaceship's clocks running slow. Also note that there's nothing wrong with the clocks and rules. Space itself is shortened and time itself is slowed down for a moving reference frame, relative to the stationary observer. These interesting effects, which have been verified experimentally many times, are all derived from the two basic postulates mentioned above.