# Motion of hawks

I am in nature,and I am watching hawks motion. I knew it before and saw it live now,that when the hawk see the animal that wants to eat,close its feather to go faster.
I made a thought,and I would like to tell me if it is correct or anything is missed.

I think that closing its feather,make air pressure smaller because its area becomes smaller,so its power becomes bigger(F,power = P,pressure * A,area).
Also because its power becomes bigger,its acceleration becomes bigger too(F = m*a).
For that reason we have bigger speed. (a = du/dt)

Is that right?

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A.T.
I think that closing its feather,make air pressure smaller because its area becomes smaller,so its power becomes bigger(F,power = P,pressure * A,area).
F is force, not power in that equation. And making A smaller makes F smaller not bigger there.

They fold their wings to reduce the drag force, which brakes them.

I see. So we can suppose that we have two forces: F1 is hawk's force and F2 air's force ?
And after to suppose that F1 stays the same,but F2 becomes smaller cause pressure of air becomes smaller?

Am I wrong again or no?

Or maybe it is not about pressure,but it is become closing its winger the hawk,the same force as before now pushes the hawk in lesser area.
So the whole force is lesser? (air resistance with few words)

A.T.
air resistance with few words
Yes as I said.

I asked him,why air resistance becomes smaller when we minimize our area,and he answered me that it is about fluid mechanics.
Also he told me that it is a bit complicated and not so straightforward as in classic mechanic.
Is that true?

sophiecentaur