General Conservation of Momentum Problem

[pinkerpikachu]

A meteor whose mass was about 10^8 kg struck the Earth (m = 6.0 X 10^24) with a speed of about 15 km/s and came to rest in the earth. A) what was the Earth's recoil speed? B) what fraction of the meteor's KE was transformed into KE of the earth? C) By how much did the Earth's KE change as a result of this collison.


I know how to figure out part A. m1v1/m2 = v2 = 2.5 X 10^-12

A little guidance on B and C please?

 

[JoshuaR]

For part B: You know the meteor's initial KE. What is that of the earth's? You know mass of earth, and velocity of earth-meteor, so you should be able to find KE of earth. There you can find the fraction.

An additional question: Does this answer make sense? If yes, why, if not, why? What type of collision is this (elastic, inelastic, etc.)?