Suspending all the usual beliefs?

Question

Long "stick", ridgid, unbendable,dense. If someone was hovering just above the sun on silver surfers board wearing a self contained magic heat suit and he held the end of a 94 million mile long stick in his hand.... Fred holds the other end of the stick down on earth.... if the surfer pushed the stick, would Fred feel it instantaneously or would the stick actually shrink for a few minutes while the energy was being transferred between molecules?

Answer 1

It would take time for the guy to feel it.  When the person pushes on the stick, the molecules in the stick at the beginning of the stick get pushed closer to each other.  This causes a wave of compression that travels from one end of the stick to the other, so that when it reaches the Earth, the Earth has a force exerted on it by the stick.  The wave of compression travels at a finite speed, and can actually be calculated from properties of the stick.  But the important point is that it does take some time for the signal to travel.