# Speed of light

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Imagine a spaceship traveling at 99% speed of light. Inside the capsule there is a gun. when it fires, space time will be warped so that the time around the bullet is reduced to such an extent that it doesn't break the speed limit. But what if instead of a gun, a flashlight was lit?

Would it emit light like usual?

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Yes. And when those inside the spaceship measure the spead of the emitted light, they find it to be c.

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Yes. And when those inside the spaceship measure the spead of the emitted light, they find it to be c.

Why is it still c?

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Because the speed of light is invarient in all frames.

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Because the speed of light is invarient in all frames.

does that mean when the speed of bullet is .9c+v, speed of the light emitted from flashlight is c+c=c?

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does that mean when the speed of bullet is .9c+v, speed of the light emitted from flashlight is c+c=c?

No. Speeds of massive particles do not add linearly. Speed of light is always the same.

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does that mean when the speed of bullet is .9c+v, speed of the light emitted from flashlight is c+c=c?

No it means that the speed of the bullet is

$\frac{.9c +v}{1+ \frac{.9c(v)}{c^2}}$

And the light is emitted at

$\frac{c + .9c}{1+ \frac{.9c©}{c^2}} = c$

Edited by Janus

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