Temperature rise after collision

[savaphysics]

Homework Statement

Determine the fractional decrease in total kinetic energy of each set of asteroids when they collide. If the average specific heat of the material composing the asteroids is assumed to be that of ice (2.05 kJ/kg·˚C), by how much does the temperature of the asteroids rise as a result of the collision in each case?

Homework Equations

Before the collision, asteroid A (mass 1,000 kg) moved at 100 m/s, and asteroid B (mass 2,000 kg) moved at 80 m/s. (asteroid b is going i an opposite direction.)

The Attempt at a Solution

After the collision I have
(1,000 kg)(100m/s) + (2,000 kg)(-80m/s)= -60,000/3,000 =20m/s

We haven't been taught temperature after collision so this is where i am stuck

 

[haruspex]

How much KE was lost? Where has that energy gone?

 

[savaphysics]

There is no KE lost right? Since they collided and there is no external forces.

 

[haruspex]

There is no KE lost right?

In an inelastic collision you should expect work energy to be lost.
You can calculate the KE before and after.