Impact of several variables on resulting projectile motion trajectory

AI Thread Summary
To analyze the impact of variables on projectile motion, focus on comparing the mean and standard deviation of each variable's effect on the landing position. The mean indicates the average change in position due to a 1% change in a variable, while the standard deviation reflects the variability of that effect. It's crucial to avoid treating horizontal and vertical motions as independent when drag is involved, as this can skew results depending on the drag equation used. Incorporating factors like air resistance and wind speed can further refine the analysis. Understanding these statistical principles will help determine which variable has the most significant influence on the trajectory.
Badgun
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Homework Statement
I have a program to model a Projectile Motion with air resistance (numerically calculated) and also with wind influence (adding wind speed to the current speed if the projectile is above some height). I have a homework to analyze the influence of several variables on the resulting trajectory (basically the final x value when it impacts the ground). I mean variables like the weight, the drag coefficient, elevation angle or the wind.
Relevant Equations
I think there aren't any equations needed for this problem.
I was told to generate these variables (m, C, alpha, wind velocity) normally distributed and compare the random data with the result and then tell, which of the variables has the most impact. Here I am stuck, tried to compare variances, kurtosis and skewness of the data (the original variables and the final x), but I don't really know, what the numbers or the differences between them really mean. I'm not really good at statistics, like I don't understand the principles of statistics. Can you suggest me a method of comparing those influences to be able to tell which of the variables has the most influence? Thank you really much!
 
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The simplest things to understand and discuss would be the mean and the standard deviation (square root of the variance).

The mean is the average. So you are just looking at how far, on average, that effect causes the landing spot to move. Now they're on different scales but you can still say something qualitative like "a 1% change in this variable causes only a 0.5% change in the position, on average, but a 1% change in this other variable causes a 10% change".

Standard deviation measures the spread of the distribution for a given fixed value of one of the variables. Again you could try to come up with some way to compare them, like a percentage, to compare how the spread of one random variable affects the spread of the final position.
 
RPinPA said:
The simplest things to understand and discuss would be the mean and the standard deviation (square root of the variance).

The mean is the average. So you are just looking at how far, on average, that effect causes the landing spot to move. Now they're on different scales but you can still say something qualitative like "a 1% change in this variable causes only a 0.5% change in the position, on average, but a 1% change in this other variable causes a 10% change".

Standard deviation measures the spread of the distribution for a given fixed value of one of the variables. Again you could try to come up with some way to compare them, like a percentage, to compare how the spread of one random variable affects the spread of the final position.

Thank you, I didn't realize I can do that this way, I hope this will satisfy what my lector wants :)
 
Badgun said:
with air resistance (numerically calculated) and also with wind influence (adding wind speed to the current speed if the projectile is above some height).
I know you were not asking about the equations for this, but a trap some fall into is treating the horizontal and vertical motions as independent when there is drag. They can be independent, but it depends on the drag equation used (linear or quadratic).
 
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