Phy-pro 2017.docx

ACKNOWLEDGMENT I would like to express my special thanks to our school ‘Dps Gandhinagar School’, principal sir ‘Mr. Atanu Rath’, to the management team of our school who gave me the golden opportunity to do this wonderful project on the topic BERNAULLI’S PRINCIPLE, which also helped me in doing a lot of research and I came to know about so many new things. Secondly I would also like to thank my parents and friends who helped me a lot in finishing this project within the limited time.

Index

1. Pressure 2. Pascal’s Law 3. Hydraulics 4. Continuity Equation 5. Bernoulli’s Equation 6. Venturi tube 7. Atomizer 8. Conclusion 9. Bibliography + Webliography

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PRESSURE

1. 2.

Pressure is defined as force per unit area. Standard unit is Pascal, which is N/m2

3. 4.

For liquid pressure, the medium is considered as a continuous distribution of matter. For gas pressure, it is calculated as the average pressure of molecular collisions on the container.

5. 6.

Pressure acts perpendicular on the surface. Pressure is a scalar quantity – pressure has no particular direction (i.e. acts in every direction).

Pascal’s Law “When there is an increase in pressure at any point in a confined fluid, there is an equal increase at every point in the container.”

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Hydraulics

You have to push down the piston on the left far down to achieve some change in the height of the piston on the right. 1.

Pressure is equal at the bottom of both containers (because it’s the same depth!)

2. 3.

P = F2/A2 = F1/A1 and since A1 < A2, F2 > F1 There is a magnification of force, just like a lever, but work stays the same! (conservation of energy). W = F1* D1 = F2 * D2 D1 > D2

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Continuity Equation

1.

A1v1 = A2v2

2.

“What comes in comes out.”

3.

Av= V/s (volume flow rate) = constant

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Bernoulli’s Equation P+1/2ρv*v+ρgh=constant

Where p is the pressure, ρ is the density, v is the velocity, h is elevation, and g is gravitational acceleration

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Venturi Tube

1. 2. 3.

A2 < A1 ; V2 > V1 According to Bernoulli’s Law, pressure at A2 is lower. Choked flow: Because pressure cannot be negative, total flow rate will be limited. This is useful in controlling fluid velocity.

P2 + 1/2ρ v12 = P1 + 1/2ρ v12

;

ΔP = ρ/2*(v22 – v12)

Atomizer

This is an atomizer, which uses the Venturi effect to spray liquid.

•

When the air stream from the hose flows over the straw, the resulting low pressure on the top lifts up the fluid.

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Conclusion Bernoulli's law states that if a non-viscous fluid is flowing along a pipe of varying cross section, then the pressure is lower at constrictions where the velocity is higher, and the pressure is higher where the pipe opens out and the fluid stagnate. Many people find this situation paradoxical when they first encounter it (higher velocity, lower pressure). Venturimeter, atomiser and filter pump Bernoulli’s principle is used in venturimeter to find the rate of flow of a liquid. It is used in a carburettor to mix air and petrol vapour in an internal combustion engine. Bernoulli’s principle is used in an atomiser and filter pump. Wings of Aeroplane Wings of an aeroplane are made tapering. The upper surface is made convex and the lower surface is made concave. Due to this shape of the wing, the air currents at the top have a large velocity than at the bottom. Consequently the pressure above the surface of the wing is less as compared to the lower surface of the wing. This difference of pressure is helpful in giving a vertical lift to the plane.

Bibliography + Webliography

>>Help from Internet:www.sceincefare.com www.mycbsegide.com >>Help from books:Refrenced from H.C.Verma Refrenced from physics NCERT

>>Help from teachers:-

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