- #1

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## Homework Statement

A guy standing on a frictionless surface has a mass of 69.5kg including the gun he is holding. He fires a 4.2g (0.0042 kg) round at 955 m/s.

A.)Find the recoil velocity of the hunter if he fires horizontally.

B.)Find the recoil velocity of the hunter if he fires 54 degrees above the horizontal?

## Homework Equations

Impulse momentum theorem

## The Attempt at a Solution

A.)Find the recoil velocity of the hunter if he fires horizontally.

The other problems that I have are collision based. In this one, I simply don't understand how to set up the problem.

I get that before the shot the total momentum of the hunter and bullet are zero, because neither has a velocity, and momentum - mv. After the shot, I get that:

[tex]69.5(v_{hunter}) + 0.0042(v_{bullet})[/tex]

So in total I have:

[tex]0_{before shot} = 69.5(v_{hunter}) + 0.0042(955)[/tex]

[tex]0 = 69.5(v_{hunter}) + 4.011[/tex]

[tex]- 4.011 = 69.5(v_{hunter})[/tex]

[tex]-\frac{4.011}{69.5} = (v_{hunter})[/tex]

[tex]v_{hunter} = -0.0577[/tex]

Am I even doing this remotely correct?

For part B. I assume I take the horizontal component of the velocity of the bullet, but then does the hunter experience a recoil that is down and left, (if he is shooting right and up)?