Bob is strapped to a board that is moving so that ? along the length of the board is 2.0. The board and direction of relativistic motion is along the horizontal. You are standing next to a hole on a horizontal platform that he hopes to pass through (with the board’s length parallel to the platform) when he arrives. The board has length L in her reference frame. The diameter of the hole is 0.75L in your reference frame. (For the purpose of this problem, you can neglect the vertical component of the movement necessary for Bob to pass through the hole.)
a) What is the length of Bob’s board in your reference frame when he arrives? Does he pass through?
b) What is the diameter of your hole in Bob’s frame when he arrives? Can he pass through?
c) Given that you witnessed Bob passing through the hole, he must have passed through in his reference frame, as well. How?