Question

Two rods of the same proper length l₀ move toward each other parallel to a common horizontal axis. In the reference frame fixed to one of the rods the time interval between the moments, when the right and left ends of the rods coincide, is equal to Δt. What is the velocity of one rod relative to the other?

Answer 1

The coordinates of the ends of the rods in the frame fixed to the left rod are shown. The points B and D coincides when

The points A and E coincide when