Einsteins Postulates

Question 1

When does Galilean Relativity stop working ?

Answer 1

-Galilean relativity states that Newton’s laws of motion are the same in all inertial reference frames
Therefore space and time are treated as fixed and absolute
This means the time interval between two events in one frame (x, y) is the same as the time interval between another frame (x’, y’)
However, this is not what happens when we are close to the speed of light
Space and time become relative, meaning, the length of an object or a time interval depends on the frame of reference
Velocity addition works with speeds much lower than the speed of light (c)
It doesn’t work for objects travelling closer to the speed of light
According to Galilean relativity, if a rocket ship travels at 0.7c and releases a probe directly in front of it at 0.5c, a stationary observer would view this at 0.7c + 0.5c = 1.2c
However, we know that nothing can travel faster than the speed of light, so this is not possible

Question 2

What are Einstein’s 2 postulates ??

Answer 2

-The laws of physics are the same in all inertial frames of reference
-The speed of light, c, in a vacuum, is the same in all inertial frames of reference

Question 3

What does the first postulate tell us about our frame of reference?

Answer 3

-to us we are stationary in our reference frame so results of experiments on different places (train, walking) we should get the same results