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## Homework Statement

A baseball pitcher throws a fast-ball (mass 50g) to stop a bullet (mass 5g), which has been shot at him at a speed of 400m/s by an angry fan. Can the pitcher save himself by stopping the bullet with a fast-ball of 100mph assuming a perfectly inelastic head-on collision, where the bullet gets stuck in the baseball?

What is the final momentum and the final speed of the baseball+bullet system?

## Homework Equations

P = mv+mv

## The Attempt at a Solution

So I did:

Final momentum:

P= bullet = (400m/s)(0.005kg) = 2

p = fast-ball = 100mph = 44.7m/s = (44.7m/s)(0.05kg) = 2.235

Pf = 2.235 + 2 = 4.235kg.m/s

Final velocity:

If the question were find the final velocity of the bullet, I guess I´d have written 0, right (because it´s perfectly inelastic)?

But since I am being asked the final speed for both baseball +bullet system, I am attempting:

v = p/m

v = 4.235kg.m/s divided by 0.055kg (total mass) = 77m/s.

So, is that correct?