As most of you know, the drag force equation is Fd=1/2*p*Cd*V^2*Cd*Ac.(adsbygoogle = window.adsbygoogle || []).push({});

At terminal velocity, Fd equals weight. If you find the value of all the variables except Cd and V, you still won't have anything. But the terminal velocity equation is Vt= sqrrt of 2weight/p*Cd*Ac. So if V is terminal velocity, it is reasonable to conclude that V^2 is equivalent to 2W/p*Cd*Ac. So if you replace V^2 with what I've stated above, you'd get W= 1/2p*Cd*2W/p*Cd*Ac.

This equation is true, but only because it cancels out everything but W. You are left with W=W. This is useless for finding Cd. You could also do the opposite. Replace Cd with (1/V^2*2weight)

pAcCd

In this case everything cancels out too. In conclusion, this formula is useless in finding terminal velocity.

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# Drag Force Equation Useless in Finding Terminal Velocity!

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