Consider the case where a pulse hits a fixed end. I want to know the physics behind the following two phenomena
1) Why does the pulse get reflected?
2) Why does the pulse get inverted?
I somewhat understand the answer to the second question. The pulse exerts an upward force on the fixed end and by Newton's Third Law the fixed end exerts an equal and opposite force. Consequently, the particles on the rope will have a negative displacement. Regarding the first answer I think that it has to do with Principle of Superposition, but I can't quite verbalize an explanation.