We know that the drag force on an object is defined as: FD = ρ*v2*CD*A/2 , where ρ is the density of the fluid the object is travelling in, v is the velocity of the object, CD is the drag coefficient of the object and A is the surface area of the object. Rearranging the formula to find drag coefficient, we have: CD = (2*FD)/(ρ*v2*A) But suppose we needed to find the drag coefficient of an object in order to find the drag force on the object; in other words, let's say we didn't have any data on both drag coefficient and drag force. How would one find drag coefficient without using the above formula? I heard that another way to find it was: CD ≈ 0.01*θ , where θ is the angle of attack of the object in radians. What I don't like about this formula is the "≈" sign, and so I avoid using it completely. Is there another formula to find the drag coefficient of an object? Thank you.