Question
The pressure difference between two points along a horizontal pipe, through which water is flowing, is 1.4 cm of mercury. If, due to non-uniform cross-section, the speed of flow of water at the point of greater cross-section is 60 cm/s, calculate the speed at the other point. Density of mercury .
Solution
Correct option is
2.02 m/s
By Bernoulli’s theorem, we have
The speed of water will be greater at the place when the cross-section is smaller.
Here P1 – P2 cm of mercury
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SIMILAR QUESTIONS
Q1
Calculate the terminal velocity of an oil drop falling freely in air. The radius of the drop is 0.01 mm and the density of oil is . The coefficient of viscosity of air is . The density of air is negligible.
Q4
An air bubble of radius 1.0 mm rises with uniform velocity through a viscous liquid of density 1625 kg/m3. Calculate the velocity of the bubble if the coefficient of viscosity of the liquid is 10 poise and the density of air is negligible. (g = 10 m/s2).
Q5
An air bubble of radius 0.1 mm is moving upwards in water with a velocity of 0.35 cm/s. If the density of water is and gravitational acceleration is 9.8 m/s2 and the density of the air is negligible, then find out the coefficient of viscosity of water.
Q6
A small sphere falls from rest under gravity in a viscous medium, producing heat due to friction. Find how rate of production of heat does depend upon the radius of the sphere at terminal velocity.
Q7
Water at a pressure of flows at 2.0 m/s through a pipe of 0.02 m2 cross-sectional area which reduces to 0.01 m2. What is the pressure in the smaller in the cross-section of the pipe?
Q8
Water is flowing through two horizontal pipes of different diameters which are connected together. In the first pipe the speed of water is 4.0 m/s and the pressure is . Calculate the speed and pressure of water in the second pipe. The diameters of the pipes are 3.0 cm and 6.0 cm respectively.
Q9
A liquid is kept in a cylindrical vessel which is being rotated about its axis. The liquid rises at the sides. If the radius of the vessel is 0.05 m and the speed of rotation is 2 rev/s, find the difference in the heights of liquid at the centre of the vessel and at its sides.
Q10
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.