Advertisements
Advertisements
प्रश्न
Figures (a) and (b) refer to the steady flow of a (non-viscous) liquid. Which of the two figures is incorrect? Why?
Advertisements
उत्तर १
Figure (a) is incorrect. It is because of the fact that at the kink, the velocity of flow of liquid is large and hence using the Bernoulli’s theorem the pressure is less. As a result, the water should not rise higher in the tube where there is a kink (i.e., where the area of cross-section is small)
उत्तर २
(a)
Take the case given in figure (b).
Where,
A1 = Area of pipe1
A2 = Area of pipe 2
V1 = Speed of the fluid in pipe1
V2 = Speed of the fluid in pipe 2
From the law of continuity, we have:
`A_1V_1 = A_2V_2`
When the area of cross-section in the middle of the venturimeter is small, the speed of the flow of liquid through this part is more. According to Bernoulli’s principle, if speed is more, then pressure is less.
Pressure is directly proportional to height. Hence, the level of water in pipe 2 is less.
Therefore, figure (a) is not possible
APPEARS IN
संबंधित प्रश्न
Can Bernoulli’s equation be used to describe the flow of water through a rapid in a river? Explain.
In a test experiment on a model aeroplane in a wind tunnel, the flow speeds on the upper and lower surfaces of the wing are 70 m s–1and 63 m s–1 respectively. What is the lift on the wing if its area is 2.5 m2? Take the density of air to be 1.3 kg m–3.
The cylindrical tube of a spray pump has a cross-section of 8.0 cm2 one end of which has 40 fine holes each of diameter 1.0 mm. If the liquid flow inside the tube is 1.5 m min–1, what is the speed of ejection of the liquid through the holes?
In deriving Bernoulli’s equation, we equated the work done on the fluid in the tube to its change in the potential and kinetic energy. (a) What is the largest average velocity of blood flow in an artery of diameter 2 × 10–3 m if the flow must remain laminar? (b) Do the dissipative forces become more important as the fluid velocity increases? Discuss qualitatively.
Water is flowing through a long horizontal tube. Let PA and PB be the pressures at two points A and B of the tube.
Suppose the tube in the previous problem is kept vertical with A upward but the other conditions remain the same. the separation between the cross sections at A and B is 15/16 cm. Repeat parts (a), (b) and (c) of the previous problem. Take g = 10 m/s2.
What is the basis of Bernoulli’s principle?
A large number of liquid drops each of radius 'a' are merged to form a single spherical drop of radius 'b'. The energy released in the process is converted into kinetic energy of the big drop formed. The speed of the big drop is [p = density of liquid, T = surface tension of liquid] ____________.
When one end of the capillary is dipped in water, the height of water column is 'h'. The upward force of 119 dyne due to surface tension is balanced by the force due to the weight of water column. The inner circumference of the capillary is (Surface tension of water= 7 x 10-2 N/m) ____________.
Which of the following is NOT an example of the application of Bernoulli's principle?
Dynamic lift caused by spinning is called ______.
If p0 = 1.03 × 105 Nm–2, ρ0 = 1.29 kg m–3 and g = 9.8 ms–2, at what height will the pressure drop to (1/10) the value at the surface of the earth?
In the widest part of the horizontal pipe, oil is flowing at a rate of 2 m/sec. The speed (in m/s) of the flow of oil in the narrow part of the tube if the pressure difference in the broad and narrow parts of the pipe is 0.25 ρoilg, is ______ m/s.
Two wires are made of the same material and have the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 9A. If the length of wire 1 increases by Δx on applying force F, how much force is needed to stretch wire 2 by the same amount?
Explain the working of an atomizer.
