Question

A horizontal pipe carries a smoothly flowing liquid of density of 1370 kg/m 3 . At Locations 1 and 2 along the pipe, the diameters are 5.75 cm and 3.45 cm, respectively.
Is the flow speed at location 2 higher or lower than at location 1?

Answer 1

Answer:

Flow speed at location 2 higher than at location 1

Explanation:

Since the pipe carries a steady flow of liquid, its volume rate can be calculated as the following

$\dot{V} = vA = v\frac{\pi d^2}{4}$

where v m/s is the flow speed, A is the cross-section area, and d is the cross-section diameter. Therefore:

$v = \frac{4\dot{V}}{d^2\pi}$

So if the volume rate stays the same, the diameter drop at location 2, then flow speed would increase at location 2.