# Homework Help: Calculate the average recoil force exerted on the weapon during that burst.

1. Nov 1, 2009

### zhuyilun

1. The problem statement, all variables and given/known data
A soldier on a firing range fires an 8-shot burst from an assault weapon at a full automatic rate of 1000 rounds per minute. Each bullet has a mass of 7.49 g and a speed of 299 m/s relative to the ground as it leaves the barrel of the weapon.

2. Relevant equations

3. The attempt at a solution
i dont understand how 8-shot burst and 1000rounds are related
i dont know how to start this question and what basic concept should be used

2. Nov 1, 2009

### tiny-tim

Hi zhuyilun!

When a bullet leaves a gun, the gun recoils, which means that it moves backwards.

It does so because of conservation of momentum.

(and what is the relationship between force and momentum?)

3. Nov 1, 2009

### zhuyilun

i get this part now~!! thanks, but what is the relationship between 8-shot burst and 1000 rounds per second

4. Nov 1, 2009

### tiny-tim

It's telling you that the burst takes .008 seconds.