I'm trying to picture intersecting paths though. Does a faster moving black hole cause more or less damage to a target?
Imagine a black hole on the quite small end, intersecting the core of a planet. Unlike regular matter, it can't really produce bow shock through collisions, right? All the target matter in the direct path just "falls in" and in elastically reduces the black hole momentum a tiny bit?
Some matter outside the direct path could be accelerated towards the black hole but slingshot behind it, rather than into it. So this material could produce an impressive wake, with material spraying outward from the collision path and interacting with the remainder of the target.
But, all this visible chaos comes from gravity rather than more direct kinetic interactions, right? If the black hole is moving faster, doesn't the target's material gets less gravitational acceleration as it spends less time in the near field? So, if the blackhole is moving very fast, does it bore a smaller hole and have less interaction with the target? Or do other effects of relativity make this more convoluted to think about?
I'm imagining a cylindrical plug of a planet "instantaneously" disappearing, and then the remainder of the planet collapsing inward to fill the void, bouncing off itself, and ringing like a bell.
> Does a faster moving black hole cause more or less damage to a target?
When a black hole accretes matter, the matter can create tremendous radiation before it crosses the event horizon due to the atoms experiencing many effects such as rapid nuclear fusion and becoming new forms of matter such as neutronium. The precise amount of energy released depends on spin, charge, and size of the black hole, and the speed at which the matter approaches the black hole.
If a tiny black hole (Let's say 10cm across) ripped through the earth at significant speed it would be like the center of the planet momentarily became the center of a star and (hand waving a bunch of assumptions) the total energy could easily be greater than the gravitational binding energy of the planet. The planet would explode.