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Why is it dangerous to stand on the edge...

Why is it dangerous to stand on the edge of platform near the line ,when the train is passing with speed ?

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When the train is passing with speed the contact air have same velocity of train . Hence according to Bernoulli.s equation , low pressure is generated at that region whereas the pressure is more at far region .So , due to the pressure difference the force acts on person towards the train and he is pulled toward the train.
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KUMAR PRAKASHAN-MECHANICAL PROPERTIES OF FLUIDS -SECTION -C (Objective Questions) (VSQs)
  1. Which fundamental law forms the basis of Bernoullis equation ?

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  2. Write Bernoulli's principle in word.

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  3. Why is it dangerous to stand on the edge of platform near the line ,wh...

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  4. Why two rowing boats moving parallel to each other come closer (attrac...

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  5. When a fluid passes through a constricted part of a pipe ,what happens...

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  6. Why does a flag (or ensign) flutter when there is strong wind ?

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  7. Explain why roof of building flyout during stormy wind.

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  8. Why does an airplane run a certain length on the runway first before t...

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  9. Explain why bullets of gun are cylinder in shape ?

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  10. What is magnus effect ?

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  11. Give reason why mercury does not wet glass .

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  12. Why free surface of liquid tend to contract their surface ?

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  13. When drops of mercury are placed on a clean surfaces of glass , they m...

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  14. Give reason why are some insects able to walk on water surface ?

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  15. Why surface tension of antiseptics kept less ?

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  16. Explain why is hot soup more testy than the colder one ?

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  17. It is better to wash clothes in hot water than in cold water .Explain ...

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  18. Detergents is added to water for removing dirt from clothes.Explain .

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  19. Why colours and lubricating oil have less surface tension ?

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  20. Arrange the following liquids in increasing order of surface tension ....

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