- Part B Choose frame S'so that its origin is located at the center of the train. Take the direction of motion of the train (eastward) to be the positive direction of x. Let the instant when the light flashes be t =0 s. What are (2,t) and (z,), the spacetime coordinates of event A and B in S? Note that the time coordinate of an event is the time at which the event actually occurs, not the time at which an observer receives information about it (e.g. when a passenger hears the sound of the bell or the siren). Express space coordinates in meters and time coordinates in microseconds to three significant figures. Enter a value for each coordinate; separate your answers by commas. Do not enter parenthesis.

- Part B Choose frame S'so that its origin is located at the center of the train. Take the direction of motion of the train (eastward) to be the positive direction of x. Let the instant when the light flashes be t =0 s. What are (2,t) and (z,), the spacetime coordinates of event A and B in S? Note that the time coordinate of an event is the time at which the event actually occurs, not the time at which an observer receives information about it (e.g. when a passenger hears the sound of the bell or the siren). Express space coordinates in meters and time coordinates in microseconds to three significant figures. Enter a value for each coordinate; separate your answers by commas. Do not enter parenthesis.