Drag Force on a Streamlined Body

[anhchangdeptra]

Hi,

I know that the drag force on an object: Fd= 1/2 . ρ . v^2 . Cd . A

where A is the reference area.

But in the case of a streamlined body, I don't know what will be taken as the reference area. Should it be the largest cross-sectional area of the body?

 

[anhchangdeptra]

Oh sorry, in this case I'm talking about drag force caused by air resistance

 

[dauto]

Yes, the cross section area as seen from the direction of the wind