Question

A meter stick at rest makes an angle of 30.0° with the x-axis. Find the length of the meter stick and the angle it makes with the x'-axis for an observer moving parallel to the x-axis at a speed of 0.650c.

Answer 1

The angle will be 30°, if the length is 1 m, for the observer it will look like

$$1\text{ cos}30°\sqrt{1-(v/c)^2}=0.66\text{ m}.$$