An observer O is standing on a platform of length L = 90 m on a station. A rocket train passes at a relative (constant) speed of 0.96c moving parallel to the edge of the platform. Then, the observer O found that the front and back of the rocket train simultaneously line up with the ends of the plat form at a particular instant. A. In the rest frame of the observer O, what is the time necessary for the rocket train to pass a particular point on the platform?
B. What is the rest length lo of the rocket train?
C. According to another observer O on the rocket train, what is the length L of the platform?
D. Again, according to observer O' on the rocket train, how long does it take for observer O to pass the entire length of the rocket train?