II. Spatial separation vs. length A. Recall the context of the tutorial Measurement. A train moves with constant nonrelativistic speed along a straight track. The train is 12 meters long. Alan and Andy stand 12 meters apart at rest on the track Beth and Becky stand at rest at the front and rear of the train, respectively Define events 1, 2, and 3 as follows Event 1: Alan and Beth pass each other Event 2: Andy and Beth pass each other Event 3: Alan and Becky pass each other 1. Give interpretations for the magnitude of each of the following quantities; that is, tell the meaning of the number in this physical context. (Some quantities may have more than one interpretation.) Beh (Alan) Beh 2. Which of the spatial separations above can be interpreted as the length of the train? Explain. B. Suppose now that the same train moves with constant relativistic speed along the same track. The train is 12 meters long in Beth's frame. Alan and Andy stand 12 meters apart at rest on the track. Events 1-3 are the same as above 1. Identify the spatial separations that have the same interpretations as the corresponding ones in part A Identify also those for which the interpretations given above are not the same. Explain. (Alan) Beh Beh 2. Which of the spatial separations above can be interpreted as the length of the train in that frame? Explain
