Answer to Question #210460 in Mechanics | Relativity for Hye

Question

1) (a) Does motion affect the rate of a clock as measured by an observer moving with it? (b) Does motion affect how an observer moving relative to a clock measures its rate? 2) To whom does the elapsed time for a process seem to be longer, an observer moving relative to the process or an observer moving with the process? Which observer measures the interval of proper time? 3) To whom does an object seem greater in length, an observer moving with the object or an observer moving relative to the object? Which observer measures the object’s proper length? 4) Prove that for any relative velocity v between two observers, a beam of light sent from one to the other will approach at speed c (provided that v is less than c, of course). 

Answer 1

Answer:

1. a) If the observer moves with the clock, the movement does not affect the speed of the clock.

b) Time in the mobile frame of reference slows down.

2. The time interval counted in the frame of reference in relation to which the clock is at rest is less than the time interval counted in the frame of reference in relation to which the clock moves. The interval of proper time is measured by an observer moving with a clock.

3. The object seems larger in length to the observer who moves with the object. It is he who measures the true length.

4. According to the relativistic law of addition of velocities, there is no speed greater than the speed of light.