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  


Correct option is

406 cm3/s


The rate of liquid flow in non-uniform horizontal tube is given by  









         g = 980 cm/s2

         h = 8 cm. 






           = 406 cm3/s.



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