## Question

A non viscous liquid of constant density 500 kg/m^{2} flows in a variable cross-sectional tube. The area of cross section of the tube at two points *P*and *Q* at height of 3 m and 6 m are and respectively. The work done per unit volume by the force of gravity as the fluid flows from point *P* and *Q* is

### Solution

Work done per unit volume by force gravity

= – change in P.E per unit volume

#### SIMILAR QUESTIONS

Water flows into a horizontal pipe whose one end is closed with a valve and the reading of a pressure gauge attached to the pipe is . This reading of the pressure gauge falls to when the valve is opened. Calculate the speed of water flowing into the pipe.

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*g* = 10 m/s^{2}.

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