Dimensional analysis, I'm kinda lost

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coasterguy
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Homework Statement



* The force of wind acting on a body can be computed by the formula:

F = 0.00256 Cd V2 A

where:

F = wind force (lbf)

Cd= drag coefficient (no units)

V = wind velocity (mi/h)

A = projected area(ft2)

* To keep the equation dimensionally homogeneous, what are the units of 0.00256?

The Attempt at a Solution



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I'm really new to this, and the professor didn't explain it well. IDK if I did that right so far, but I'm not sure what to do next. What does it mean by the units of .00256? Thanks
 
Since you know this already, I will answer your question with another question.

What is the full definition of [tex]C_d[/tex] ?

What 2 important variables are missing to non-dimensionalize that term there?

As your topic implies, check your units.