When e.g. an asteroid hits a black hole is there any possibility of a temporary recoil of impacted material? When e.g. an asteroid hits a black hole is there any possibility of a temporary recoil of impacted material?Or in that case the material just suddenly stops its movement?
 A: From the perspective of the infalling asteroid, there is nothing special about the event horizon. There is no surface to "hit" or recoil from. The asteroid just falls straight through the horizon towards the singularity, in a finite amount of time.
From the perspective of an outside observer, time dilation of information from the asteroid prevents you from ever observing the event where the asteroid crosses the event horizon. The outsider's perspective is that the asteroid asymptotically approaches the horizon and sticks to it. Then the ever-increasing redshift makes its spectrum grow redder and colder forever.
(An interesting calculation is to assume your infalling object has any finite temperature $T$ and to compute the evolution of its apparent temperature $T_\text{app}$ thanks to the near-horizon redshift. After a finite amount of time, the apparent temperature will fall below the Hawking temperature of the black hole, $T_\text{app}<T_H$.  Presumably after this point the thermal noise from the black hole will obscure any light from your object, and you won't be able to "see" it approaching the event horizon any more.)
This is really fundamentally different from "impacting" a black hole in a way that could cause a shock within the asteroid to send ejecta backwards. However, you might be amused to read about accretion disks and the jets they can produce.
A: As far as I'm aware, if an object went into a black hole the material would do neither. A black hole isn't a brick wall- it is just a region of space where gravity is so strong that light doesn't escape.
