Direction of Light - Laser Beam Moving Sideways at Relative Speed

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SUMMARY

The discussion centers on the behavior of a laser beam emitted from a moving car, specifically when the car is moving sideways at a relative speed. Participants explore two scenarios: one where the beam follows the emitter's forward direction and another where the beam appears to move at an angle relative to an observer in the rest frame. The consensus indicates that the laser beam will indeed follow the direction of the emitter, resulting in an angled trajectory relative to the stationary observer, consistent with the principles of relativity.

PREREQUISITES
  • Understanding of basic principles of relativity
  • Familiarity with the concept of light propagation
  • Knowledge of reference frames in physics
  • Basic comprehension of laser technology
NEXT STEPS
  • Study Einstein's theory of special relativity
  • Learn about the concept of simultaneity in different reference frames
  • Investigate the behavior of light in non-inertial frames
  • Explore practical applications of lasers in moving systems
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Physics students, educators, and anyone interested in the implications of relativity on light behavior and motion dynamics.

disregardthat
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If you send a laser beam in a car at a plate while moving it sideways at a relative speed, how will the beam act?

a) Will it follow the forward direction of the emitter and hit the plate? (The rest frame will see it move directily forward and see it not hitting the plate)

b) If the rest-frame saw this, would he see the beam move in a sloped angle compared to himself, (a straight angle towards the plate in the car)

I am just reading the introduction to relativity... You all know the illustration of the train and the beam that moves "sideways" to show how a clock is slowed down. But it just makes me wonder that light will follow the emitters sideway velocity. Shouldn't it be "detatched" from the moving frame and move directly forward. Or does it move at an angle so in both cases it hits the direct point of aiming for the laser.
 

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