# Projectile Cube

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1. Oct 28, 2014

### Mike Jones

We have a solid cube with some mass that we fire as a projectile at some angle. The cube is launched in such a way that two of the faces are perpendicular to the initial velocity vector. Assuming there is air resistance, would the cube change its orientation while it flies, even if the mass is balanced throughout the cube? If not, how can we find the cross sectional area at any given time?

2. Oct 28, 2014

### OldEngr63

If two planes are each perpendicular to a specified vector, they are either the same plane or they are parallel to each other.

I don't think you said what you meant. Would you try again, please?

3. Oct 28, 2014

### Danger

I can't answer your last question; in fact, I doubt that it can be answered. You'd have to have multiple laser scanners tracking the thing constantly.
I will say, just in case your basic goal is weapons development (either real or fictional), that what you've described is one of the worst possible designs for a firearms projectile. Beside its inherent instability, you can't effectively impart the twist that goes into spin-stabilizing a real bullet. Outside of any man-made considerations, remember that air is a dynamic fluid medium, not a constant. A 1 km/hr change in wind speed can throw something off target by a huge amount.

4. Oct 28, 2014

### 256bits

5. Oct 29, 2014

### Danger

That's an excellent link, 256bits, with lots of really nice secondary links.

6. Oct 30, 2014

### Mike Jones

Basically, I'm wondering if it's possible to predict the orientation of a cube as it flies through the air. Based on the responses, it seems as though there are too many variables for such as predictive function to exist without producing inaccurate results.

Thank you for the link though! Very cool.

7. Oct 30, 2014

### Danger

I'm guessing that it would be about the same as sending someone into a tornado in a hang-glider and trying to predict where he'll puke.