The flow of blood in a large artery of an anesthetised dog is diverted through a Venturi meter. The wider part of the meter has a cross-sectional area equal to that of the artery. A = 8 ${\mathrm{mm}}^2$. The narrower part has an area a = 4 ${\mathrm{mm}}^2$. The pressure drop in the artery is 24 Pa. What is the speed of the blood in the artery?

(Density of blood = $1.06\times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$)

1.   145 m/s

2.   0.145 m/s

3.   123 m/s

4.   0.123 m/s

A fully loaded Boeing aircraft has a mass of $3.3\times {10}^5$ kg. Its total wing area is 500 ${\mathrm{m}}^2$. It is in level flight with a speed of 960 km/h. The pressure difference between the lower and upper surfaces of the wings is: [Given: Density of air, ρ = 1.2 ${\mathrm{kgm}}^{-\mathrm{3\; }}$and g = 9.8 m/s²]

1.  $6.5\times {10}^4 {\mathrm{Nm}}^{-2}$

2.  $6.5\times {10}^3 {\mathrm{Nm}}^{-2}$

3.  $6.5\times {10}^5 {\mathrm{Nm}}^{-2}$

4.  $5.5\times {10}^5 {\mathrm{Nm}}^{-2}$

A fully loaded Boeing aircraft has a mass of $3.3\times {10}^5$ kg. Its total wing area is 500 ${\mathrm{m}}^2$. It is in level flight with a speed of 960 km/h. The fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface is:

1.  0.008

2.  0.08

3.  0.8

4.  8.0