How significant is the material in drag force calculations?

Question

I went to Wolfram's "Drag Force Calculator" and received 4900 newtons for a cone that has a radius of 3 meters and a height of 3 meters, moving through air at a standard pressure, 15 celsius, at a speed of 20 m/s.

I looked up the cone drag coefficient and it was 0.50, and it does not appear that any further information is required. The material does make a difference, of course, but is the difference so miniscule that it's not worth adding?

David Hammen · Answer

As the material of which something is made of affects an object's mass, given two objects with different densities but with exactly the same surfaces (size, shape, texture), the more dense object will be subject to less drag deceleration. Surface shape and texture are important factors as well. This is, for example, why dimples on golf balls are highly regulated, why baseballs scuff with dirt are highly prized by pitchers (and tossed by umpires), and why airplane engineers are constantly toying with slight changes to the shape of a wing.

An exception to the above occurs above the Karman line. Shape and texture don't matter nearly as much in the very thin air of the upper atmosphere. Just about everything has a coefficient of drag of 2.2 (or higher) in the thermosphere.

How significant is the material in drag force calculations?

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