Airplanes dropped in different orientations, or in a way that’s sensitive to initial conditions and leads to B gliding while A stalls. B is dropped from right above a passing eagle and gets carried off to Mordor. They’re “dropped” far out past geostationary orbit so that “stationary relative to the planet” in fact means that they’re flung off into space, and only reach Earth by getting slingshotted around other planets. Both are dropped over Brazil with notes to please throw them into the Atlantic, and A is dropped so that its coriolis motion as it falls will push it to a more visible area. They’re microscopic black holes dropped from the other side of the earth.
Since you clearly have something in mind, once you reveal it, are we going to go “Oh, yeah, that’s much more sensible than the gliders that are dropped near the boundary of glide vs. stall air pressure,” or are we going to go “well, that’s arbitrary.”
Rigid hot-air-balloon shapes that start out at 1500 Celsius and fall to earth once they are no longer keeping the air under them hot. Seed crystals in a hailstorm. Any object that falls faster if broken and will break if dropped from the higher altitude. Solid-state electrostatic thrusters pointed downward, that arc and fail if the pressure is too high. Spinning propeller craft thrusting downward that undergo a laminar to turbulent transition if the pressure is too high.
The problem specified “freefall”, so thrusters are out. But I agree that it’s underspecified—there are way too many things which fit so we are reduced to guessing what Thomas had in mind.
The initial conditions did not forbid dropping object A into a downdraft and object B into an updraft :-)
But here is another attempt: objects A and B open parachutes 3 seconds after passing altitude X. Object B starts at altitude X, accelerates from zero for three seconds, and then radically slows down. Object A starts higher, so when it passes altitude X it is already going fast and so in three seconds is capable of passing B which is already braked by a parachute.
Airplanes dropped in different orientations, or in a way that’s sensitive to initial conditions and leads to B gliding while A stalls. B is dropped from right above a passing eagle and gets carried off to Mordor. They’re “dropped” far out past geostationary orbit so that “stationary relative to the planet” in fact means that they’re flung off into space, and only reach Earth by getting slingshotted around other planets. Both are dropped over Brazil with notes to please throw them into the Atlantic, and A is dropped so that its coriolis motion as it falls will push it to a more visible area. They’re microscopic black holes dropped from the other side of the earth.
There is some wit here, but no proper solution.
Since you clearly have something in mind, once you reveal it, are we going to go “Oh, yeah, that’s much more sensible than the gliders that are dropped near the boundary of glide vs. stall air pressure,” or are we going to go “well, that’s arbitrary.”
Rigid hot-air-balloon shapes that start out at 1500 Celsius and fall to earth once they are no longer keeping the air under them hot. Seed crystals in a hailstorm. Any object that falls faster if broken and will break if dropped from the higher altitude. Solid-state electrostatic thrusters pointed downward, that arc and fail if the pressure is too high. Spinning propeller craft thrusting downward that undergo a laminar to turbulent transition if the pressure is too high.
As Lumifer said, “freefall” and as the initial conditions say—rigid bodies.
The problem specified “freefall”, so thrusters are out. But I agree that it’s underspecified—there are way too many things which fit so we are reduced to guessing what Thomas had in mind.
It is not what I have in mind. Anything goes, which does not break the initial conditions.
The initial conditions did not forbid dropping object A into a downdraft and object B into an updraft :-)
But here is another attempt: objects A and B open parachutes 3 seconds after passing altitude X. Object B starts at altitude X, accelerates from zero for three seconds, and then radically slows down. Object A starts higher, so when it passes altitude X it is already going fast and so in three seconds is capable of passing B which is already braked by a parachute.
Yes, well. There is some wit here again. The best solution I have in mind don’t require an atmosphere at all.
Well, maybe just for the sake of the liquid ocean water. Which is only for the sake of “a mountain and a valley soulution” prevention.