I have two values for the initial velocity of a projectile through water. One is measured experimentally and the other a theoretical value for initial velocity.(adsbygoogle = window.adsbygoogle || []).push({});

The measured value is 23.75m/s

The theoretical value is 26.3m/s Resistance forces were not accounted for in this calculated value.

To account for resistance forces I can use the difference in these values.

Is it acceptable to revise the Drag Equation (Drag force=C_{d}* A * .5 * r * V^{2}) to calculate the Coefficient of Drag as a function of velocity rather than force?

C_{dvel }= Drag velocity / (A * .5 * r * V^{2})

Where V=Theoretical Initial Velocity

In this way I can account for the difference in theoretical and measured initial velocity by assuming it is as a result of resistance forces. The new equation will read:

Drag velocity = C_{dvel}*A * .5 * r * V^{2}

It seems like I'm probably fiddling with something I shouldn't mess with, but it does make my calculated initial velocity more accurate. Not the most elegant solution I'll admit, but it kinda works.

ANY, advice/corrections appreciated,

Thanks

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# Manipulating the Drag Equation

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