I was thinking of this thought experiment the other day and it didnt quite seem to make sense to me. I hope some of you can explain it. I have drawn a quick example of the setup:(adsbygoogle = window.adsbygoogle || []).push({});

and sorry for my english

(c = 1 m/s)

Imagine a 1 meter long spaceship with a velocity of 0,5 m/s (c/2). The spacesip has two light sensors attached to it, one in the front and one in the back. Each of these sensors has clocks attached to them (A and B on the drawing) and when the sensors register a photon the clocks will stop. The clocks are synchronized and they tick once each second.

Now imagine a photon coming towards the spaceship ofcourse with a velocity of c (1 m/s). It hits the first sensor and clock (B) stops. The photon continues through the spaceship and hits the other sensor and clock (A) stops. Now since the speed of light must always be the same for all observers the two clocks must now differ by one second.

But here is my question,.. according to SR the clocks on the spaceship ticks slower (from our point of view) because they are moving, and if the clocks has to differ by one second, time must go 'faster' (and definately not slower) for the moving spaceship..

thx in advance for an answer,, and sorry for not expressing me perfectly.. pls ask if you have any questions yourself

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# Thought experiment (SR)

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