- #1

- 23

- 1

**Question Part 1:**

A machine gun fires a stream of bullets into a block that is free to move on a horizontal frictionless tabletop. Each bullet has mass 66 grams; their speed is 930 m/sec, and the block a mass of 7.36 kg. After 15 bullets, the speed of the block is?

**Calculation Part 1:**

[tex]\frac{(0.066 kg * 15 bullets)}{(0.066 kg * 15 bullets) + 7.36 kg}=110.263 m/sec[/tex]

**Question Part 2:**

If a man in the previous statement can exert an average force of 180 N against the gun, determine the maximum number of bullets he can fire per minute.

**Attempt to Calculate:**

I am unsure of how I would go about this. I attempted to think of it as a reverse of the previous question, but what didn't work out was getting bullets per minute without figuring out a basic equation then using sample bullets/minute numbers to see where the breaking point of 0 m/sec is. Also, I kept in mind the need to change the velocity of m/sec to m/min if needed.

The equation I attempted to use was:

[tex]V_{gun+man}=\frac{m_{bullet}*numberofbullets}{(m_{bullet}*numberofbullets)+M_{man}}v_{bullet}[/tex]

Any help with where to start?