In deriving Bernoulli's equation , we equated the workdone on the fluid in the tube to its change in the potential and kinetic energy (a) How does the pressure change as the fluid moves along the tube if dissipative forces are present ? (b) Do the dissipative forces becomes more important as the fluid velocity increase? Discuss qualitatively.

Explanation

(a). If dissipative forces are present, then some forces in liquid flow due to pressure difference is spent against dissipative forces, due to which the pressure drop becomes large
(b). The dissipative forces become more important with increasing flow velocity, because of turbulence.