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Old 10-12-2023, 03:55 PM   #15 (permalink)
Ecky
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Not correct.

The coefficient of drag is a unitless and dimensionless number. What it describes is the shape, not the size.

For example, a battleship might have a coefficient of drag of 0.32, but you and I both know it doesn't have less drag than a Crown Vic. What it says its, if a battleship were shaped like a Crown Vic instead, it would have more drag.

A cube has a coefficient of drag of ~1.0. So, by the Explorer having a drag coefficient of 0.41, that indicates it only has~41% as much drag as if it were cube shaped.

Getting the size off Google, a Ford Explorer is 1.80 meters tall, and 1.88 meters wide. A Crown Vic is 1.44 meters tall and 1.98 meters wide.

To get the frontal area that these vehicles have to push through the wind, you multiply the width by the height. The Explorer ends up with an area of 3.68 meters squared, while the Crown Vic's area is 2.85 meters squared. 3.68 / 2.85 = 1.3, meaning the Explorer is 1.3x larger in the wind, even before you take its drag coefficient into account

The Explorer is 3.68 meters squared facing the wind, but it has the drag coefficient of 0.41. 3.68 x 0.41 = 1.51, its total drag.

The Crown Vic is 2.85 * 0.37 = 1.05, its total drag.
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