An ideal liquid flows through a horizontal tube of variable diameter. The pressure is lowest where the . . . . . . .

The speeds of air above and below the wing of an airplane are $120\, m/s$ and $90\, m/s$,respectively. The density of air is $1.3\, kg/m^3$. If the wing has a length of $10\, m$ and a width of $2\, m$,the pressure difference between the top and bottom of the wing is ......... $Pascal$.

$A$ closed water tank has a cross-sectional area $A$. It has a small hole at a depth of $h$ from the free surface of the water. The radius of the hole is $r$ such that $r \ll \sqrt{\frac{A}{\pi}}$. If $p_o$ is the pressure inside the tank above the water level and $p_a$ is the atmospheric pressure,the rate of flow of the water coming out of the hole is ($\rho$ is the density of water).

Water flows through a frictionless duct with a cross-section varying as shown in the figure. The pressure $p$ at points along the axis is represented by:

State Bernoulli's principle in words.

The figures below show water flowing through a horizontal pipe from left to right. Note that the pipe in the middle is narrower. Choose the most appropriate depiction of water levels in the vertical pipes.