a 10 kg ball moving due west at 2m/sec collides with a 4kg ball that is moving due east at 3 m/sec. You determine that immediately after the collision the 10 kg ball is moving due west at 0.57 m/sec.

A) this probably IS a Totally inelastic collision
B) this definitely is NOT a Totally inelastic collision
C) More information is needed to determine the likely nature of the collision.

3 answers

Easy. Use conservation of momentum due west.

10*2-4*3=10*.57 + 4V
solve for V

Now, check energy before and after.
1/2 10&2^2+1/2 *4*3^2=? 1/2 10*.57^2+1/2 4*V^2

Thanks! :)

v=0.575m/s