The diameter of each of the five bronchi after the fourth branching is 10 mm. The tidal volume breathed is Q inhaled over 0.5 s. Density of air is 1.2kg/m3 and viscosity is 1.78X10-5 Kg/(m.s). 1 L/s = 0.001 m3/s.
a.If Re is 1200, explain if the flow be laminar or turbulent. Calculate the magnitude of Q?

b.Using the same breathing parameters, explain whether flow through the trachea is laminar or turbulent if Re is 4800. Determine the diameter of trachea.

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