Draw a diagram and answer all the parts correctly and in detail.vWhy are the for

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Draw a diagram and answer all the parts correctly and in detail.vWhy are the formulas being used.

51. BIO When it is threatened, a squid can escape by expelling a jet of water, sometimes colored with camouflaging ink. Consider a squid originally at rest in ocean water of constant density 1 030 kg/m3. Its original mass is 90.0 kg, of which a significant fraction is water inside its mantle. It expels thi:s water through its siphon, a circular opening of diameter 3.00 cm, at a speed of 16.0 m/s. (a) As the squid is just start- ing to move, the surrounding water exerts no drag force on it. Find the squid's initial acceleration. (b) To estimate

Explanation / Answer

Here, first of all, we need to find flow rate

Q = v * A

where v is velocity and A is area

Q = 16 m/s * pi*0.0152

Q = 0.01131 m3/s

Mass flow rate = Q * density

Mass flow rate = 0.01131 m3/s * 1030 kg/m3

Mass flow rate = 11.649 kg/s

as the water is ejected, the mass varies, so we can write

F = dm/dt * v

F = 11.649 kg/s * 16 m/s

F = 186.38 N

from newton's second law

a = F/m

a = 186.38/90

a = 2.07 m/s2 <----------------- This is the acceleration

Now, assuming that the force is equal to the drag force exerted,then we have

186.38 N = 1/2 * 1030 * 0.3 * 0.08 m2 * v2

notice that I have converted cross sectional area to m2.

Now solving for v, we get

v = 3.88 m/s

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