Transformation of Angles (Relativity)

Phyrrus
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Homework Statement


Find and compare the transformations of the angle of the velocity vector of a particle and the angle of an inclined stick. The relationship between the two frames is as usual.

In frame S' a stick makes an angle of θ' with the x' axis. What is the angle θ measured in the S frame? What is the length in the S frame?

Homework Equations



x' = xcosθ + ysinθ
y' = -xsinθ + ycosθ ?

The Attempt at a Solution



I really have no idea what the question is really asking. Thanks.
 
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Hi Phyrrus! :smile:
Phyrrus said:
Find and compare the transformations of the angle of the velocity vector of a particle and the angle of an inclined stick.

When an observer measures the direction of a line (such as this stick), he does so at a constant time in his frame.

(you can think of a line as a point traveling at infinite speed in the observer's frame! :biggrin:)

A constant time in his frame is not a constant time in the new frame. :wink:
 
thanks mate
 
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