Question

2 kg and 3 kg objects slide together, and then they break apart. If the final velocity of 2 kg is 10 m/s,

a) Find the velocity of object 3 kg.
b) Find the total change in the kinetic energies of the objects.

Answer 1

P = (2 + 3) * V where V is their initial speed (total momentum)

P = 2 * 10 + 3 * Vx where Vx here would be V3

If the initial momentum is not known how can one determine the final velocity of the 3 kg obj.

Also work depends on the sum of the velocities

W (initial) = 1/2 (2 + 3) V^2 the initial kinetic energy

W (final) = 1/2 * 2 * V2^2 + 1/2 * 3 * V3^2

It appears that more information is required for this problem