Galilean transformation and contradictions with light | Physics | Khan Academy

Here we'll see how classical physics predicts scenarios that disagree with what we observe in nature. Something's got to give….

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[setarehsaremi]

I am confused in the last part, we say that the photon is moving slower at Sally's frame of reference, but when we want to plot its path, we consider the light velocity 3*10^8, shouldn't it be half of this.
My question is that why the photon (in galilean form) still has the speed of light in Sally's frame?

[tomt]

Hi Sal and Team, could you please show the order of these spacetime videos?Thanks for the awesome work!

[ArunNairk_EE_]

Why photon from the flashlight is not moving with speed c/2 with respect to her frame of reference

[jacobvandijk]

Sal is confusing us by saying that Sally is in the S'-frame (single prime), while he is making calculations for her in the S''-frame (double prime), the spaceship in front of her.

[שלומיבדיחי-נז]

So special relativity says that the speed of light is always c in an inertial frame of reference, but what if I'm not inertial, what if I'm shooting a photon and then accelerating towards it? Let's say I'm going to almost instantly, will light look slower to me during/after the acceleration phase?

[comicrelief]

What is a photon? A representative model of light propagation?
How does one measure its speed?

[jettburns]

Fascinating video! Where can I find this on Khan Academy? Has it even been put on the website?

[thetheoreticalphysicist]

Conclusion: Light speed appears the same to every observer regardless of their speed...