A 2700-kg car traveling at 30 m/s collides with a 1600-kg car at rest at a stop sign. If the 2700-kg car has a velocity of 7.5 m/s after the collision, find the velocity of the 1600-kg car after the collision.

Explanation:

There are generally two types of collisions between objects - elastic and inelastic.

Elastic collisions are those that converse kinetic energy. Inelastic are those that do not conserve kinetic energy.

In the ideal inelastic collision and elastic collisions, momentum is conserved.

Typically, ideal inelastic collisions are represented when both masses stick together after the collision.

The problem statement gives no indication that this is an ideal inelastic collision (the cars stick together) or an inelastic collision (no energy degradation expression is given). Therefore, we should assume that the cars are experiencing an elastic collision.

Since both momentum and kinetic energy are converved, we can observe that...

where v is the initial velocity and u is the final velocity (after the collision)

The problem statement gives us three of the four unknowns. So we can easily apply either equation to solve the the velocity of the 1600-kg car after the collision. Momentum is easier to work with.

root word, prefixes, and suffixes