Question

The pressure in a moving stream of fluid
a. is greater than the pressure in the surrounding fluid.
b. is less than the pressure in the surrounding fluid.
c. depends on the nature of the fluid.
d. depends on the volume of the fluid.

Answer 1

I think it's a) and b). The difference in pressure is the reason for the fluid to move.

Answer 2

Let's take a look at Bernoulli's Principle.

\[{v^2 \over 2} + gz + {p \over \rho} = \rm const.\]

If we increase the velocity in incompressible flow (that is to say that \(\rho = \rm const.\)) and the fluid flows without gaining any height (that is to say that \(gz = \rm const.\)) the pressure must do what such that Bernoulli's Principle equation remains constant?