Question

Without looking at them, how would one distinguish between an object with a mass of 10 kg and an object with a mass of 2 kg in outer space?

Answer 1

by measuring the acceleration?
F=ma, we can see which one accelerate slower after applying the same force to both objects
or maybe if you know the density, it's m= density* volume

Answer 2

Does that apply when there's no (or very little) gravity?

Answer 3

as force, i meant doing something like pushing them, or pulling them, or hitting them with something ( momentum). Otherwise, I think it's impossible to measure without knowing the density, or the ability to touch them with something. At least, not by seeing the spectrum of the elements. So yes, it will work without gravity. As long as you can see how it reacts to a force. a

Answer 4

imagine playing pool. The forces are in the horizonal direction,independent of gravity. If you hit a 2kg ball vs. a 10 kg ball, you will see the difference right away :) Would you not?