Hey guys, I wondered if you could give me a hand with this?(adsbygoogle = window.adsbygoogle || []).push({});

1.A marksman follows a rapidly moving target by swinging his rifle from left to right about a vertical axis whilst holding the barrel horizontal. Just as the bullet is about to leave the barrel it has a muzzle velocity of 800 ms^{-1}.

- If, at this instant, the rifle is rotating at 1 rad/s, what is the magnitude of the Coriolis force on the 20g bullet?
- Find the direction of force the rifle barrel exerts on the bullet.

As far as I can see, the only relevant equation is that for the Coriolis pseudoforce:

[tex]\vec{F}=-2m\vec{\omega}\times\vec{v}[/tex]

Where F is the coriolis force, m is the mass of the bullet (0.02 kg), omega is the angular frequency of the rifle and v is the muzzle velocity.

I assumed I don't have to take into account the coriolis effect due to the rotation of the earth (negligible compared to the rotation of the rifle) and plugged in the numbers for the first part to get -320N. This seems like an awfully large number and I just want to check that I have it right.

As for the second part, the muzzle is exerting a force on the bullet in the direction of rotation up until the point the bullet leaves the muzzle, after which there is only the Coriolis pseudoforce acting perpendicular to both the axis of rotation (vertically down) and the direction of motion (radial in x-y plane) such that the bullet is deflected to the marksman's left (I think...). Which of these forces is the one they're asking for?

Thanks in advance. :)

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# Homework Help: Coriolis Force On A Bullet

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