Question

If two blocks of equal mass are traveling with equal and opposite velocity collide inelastically, what is their final velocity?

Answer 1

A.Less than what they started with.
B.The same as what they started with.
C.0 m/s

Answer 2

Inelastic collisions mean that their total kinetic energy is not the same before and after the collision, but momentum is still conserved.

By the symmetry of the set up (mass, velocity), we can deduce that both of them should have the same final velocity, but in an inelastic collision, some kinetic energy is converted into other forms of energy, and so the final velocity is less than what they started with.

Note that in a perfectly inelastic collision they will lose all their kinetic energy.

Answer 3

so since inelastic collisions lose all their kinetic energy then would it be 0?

Answer 4

@Festinger

Answer 5

In inelastic collision where they lose all their kinetic energy (called perfectly inelastic collision), their total kinetic energy is 0 after collision.

I don't know if it loses all their kinetic energy in your original question since there isn't the words "perfectly inelastic collision", so the safer bet would be to put A.

Answer 6

ok thanks!