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Explain why (a) To keep a piece of pap...

Explain why
(a) To keep a piece of paper horizontal ,you should blow over , not under , it

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When we blow over the of paper , the velocity of air increases . As a result , the pressure (P) on it decreases in accordance with the Bernoulli.s theorem whereas the pressure below remains the same as atmospheric presseure Pa. Thus , the paper remains horizontal.
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KUMAR PRAKASHAN-MECHANICAL PROPERTIES OF FLUIDS -SECTION - B Numerical From Textual Exercise
  1. For a fluid in a steady flow , the increase in flow speed at a constri...

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  2. For the model of a plane in a wind tunnel , turbulence occurs at a …. ...

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  3. Explain why (a) To keep a piece of paper horizontal ,you should blow...

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  4. When we try to close a water tap with our fingers , fast jets of water...

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  5. The size of the needle of a syringe controls flow rate better than the...

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  6. A fluid flowing out of a small hole in a vessel results in a backward ...

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  7. A spinning cricket ball in air does not follow a parabolic trajectory

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  8. A 50 kg girl wearing high heel shoes balances on a single heel . The h...

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  9. Torricell 's barometer used mercury . Pascal duplicated it using Frenc...

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  10. A vertical offshore structure is built to withstand a maximum stress o...

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  11. A hydraulic automobile lift is designed to lift cars with a maximum ma...

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  12. A U- tube contains water and methlated spirit separated by mercury . ...

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  13. In the previous problem , if 15.0 cm of water and spirit each are furt...

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  14. Can Bernoulli's equations be used to describe the flow of water throu...

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  15. Does it matter if one uses gauge instead of absolute pressures in appl...

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  16. Glycerine flows steadily through a horizontal tube of length 1.5m and ...

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  17. In a test experiment on a model aeroplane in a wind tunnel , the flow...

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  18. Figures (a) and (b) refer to the steady flow of a (non -viscous) liqu...

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  19. The cylindrical tube of a spray pump has a cross -section of 8.0cm^(2)...

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  20. A U -shaped wire is dipped in a soap solution, and removed . The thin ...

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