Albert has a flashlight in each hand and directs them at the front and rear ends of the freight car. Albert switches the flashlights on at the same time.
In Albert's frame of reference, which beam of light travels at a greater speed, the one directed toward the front of the one toward the rear of the train, or do they travel at the same speed?
Which beam travels faster in your frame of reference?
Enter the answers for Albert's frame of reference and your frame of reference separated by a comma using the terms front, rear, and same. For example, if in Albert's frame of reference the beam of light directed toward the front of the train travels at a greater speed and in your frame of reference the two beams travel at the same speed, then enter the front, same.