# Find the average force required to hold the gun in position

#### Joe_1234

##### New member
A gun fires 6 bullets per second into a target. The mass of each bullet is 3g & the speed of 500 m/s. Find the average force required to hold the gun in position.

#### skeeter

##### Well-known member
MHB Math Helper
Impulse equation ...

$F \cdot \Delta t = m \cdot \Delta v$

#### HallsofIvy

##### Well-known member
MHB Math Helper
You titled this "momentum" so it looks like you already knew the basic idea. The momentum of a single bullet is "mass times velocity" and you are given both of those. Of course, the momentum of 6 bullets is 6 times the momentum of a single bullet. Since this all happens in one second, divide by one second to get the force.

Be careful to use consistent units. You are given the mass in grams and the speed in m per second. Either convert mass to kg to get the force in Newtons or convert the speed to cm per second to get the force in dynes. I recommend the former.

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#### skeeter

##### Well-known member
MHB Math Helper
You titled this "momentum" so it looks like you already knew the basic idea. The momentum of a single bullet is "mass times velocity" and you are given both of those. Of course, the momentum of 6 bullets is 6 times the momentum of a single bullet. Since this all happens in one second, divide by one second to get the force.
calculating the impulse for one bullet over $\Delta t = \frac{1}{6} \text{ sec}$ yields the same result as six bullets in $\Delta t = 1 \text{ sec}$