Aspace probe with a rest mass of 8.1×10^7 kg and a speed of 0.49c smashes into an asteroid at rest and becomes embedded within it. if the speed of the probe-asteroid system is 0.26c after the collision, what is the rest mass of the asteroid? answer in kg.

m = 8.81*10^7 kg

Explanation:

relative momentum

momentum prior to collision is given as

Pi = 4.553 *10^7 c

let mass of asteroid is m, then final momentum is

Pf = 0.26926 (8.1*10^7 + m) * c

from conservation of momentum

Pi = Pf

4.553 *10^7 c = 0.26926 (8.1*10^7 + m) * c

m = 8.81*10^7 kg

i think the answer is a, hope this is right, that would be my best guess.