The Sliding Ladder Problem
A ladder is leaning against a wall. The base of the ladder starts to slip
while the top of the ladder remains in contact with the wall. How does the rung
halfway up the ladder move in space as the ladder slips?
Can you prove your answer?
How do the other rungs move? What can you say about the path they
take as the ladder slips? Can you prove your answer?
[Slide the base of the ladder by dragging the BLACK point. Slide the point whose path you
want to trace by sliding the RED point.]