A Non Viscous Liquid Of Constant Density 500 Kg/m2 flows In A Variable Cross-sectional Tube. The Area Of Cross Section Of The Tube At Two Points Pand 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   

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A non viscous liquid of constant density 500 kg/m2 flows in a variable cross-sectional tube. The area of cross section of the tube at two points Pand 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   


Correct option is


Work done per unit volume by force gravity 

            = – change in P.E per unit volume  








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.


Air is streaming past a horizontal aeroplane wing such that its speed is 120 ms–1 at the upper surface and 90 ms–1 at the lower surface. If the density of air is 1.3 kg/m3, find the difference in pressures between the two surfaces of the wing. If the wing is 10 m long and has an average width of 2 m, then calculate the gross lift on it.      


A horizontal tube has different cross-sectional areas at points A and B. The diameter of A is 4 cm and that of B is 2 cm. Two manometer limbs are attached at A and B. When a liquid of density 0.8 g/cm3 flows through the tube, the pressure-difference between the limbs of the manometer is 8 cm. calculate the rate of flow of the liquid in the tube. (g = 980 cm/s2  



Find out the velocity of efflux of water from a hole in the wall of a tank made at 20 m below the free surface of water in the tank.

g = 10 m/s2.


Water tank has a hole in its wall at a distance of 10 m below the free surface of water. The diameter of the hole is 2 mm. Compute the velocity of efflux of water from the hole and the rate of flow of water. (g = 9.8 m/s2


S1 and S2 are spring balances. A block A is hanging from spring balanceS1 and immersed in a liquid L which is contented a beaker B. The mass of beaker B is 1 kg and the mass of liquid L is 1.5 kg. The S1 and S2balances reads 2.5 kg and 7.5 kg respectively. What will be the reading ofS1 and S2 when the block A is pulled up out of the liquid :  


Air is blow through a pipe AB at a rate of 15 liter per minute. The cross section area of the wide portion of the pipe AB is 2 cm2 and that of the narrow potion is 0.5 cm? the difference in the water level h is :    


Water from a tap emerge vertically downward with a initial speed of 1 m/s. The cross section area of the tap is 10–4 m2. Assume that the pressure is constant throughout the stream of water and that the flow steady. The cross section area of the stream 0.15 m below the tap is : 


A pipe GB is fitted with two pipes C and D. The pipe has area A = 24 m2at G and velocity of water at G is 10 m/s and at C is 10 m/s the velocity of water D is 


Water flows along a horizontal pipe whose cross section is not constant. The pressure is 1 cm of Hg where the velocity is 35 cm/s. At a point where the velocity is 65 cm/s. At a point where the velocity is 65 cm/s, the pressure will be: