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When air plane fly at higher altitude it...

When air plane fly at higher altitude it is not right to keep a fountain pen in a pocket.

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As the altitude increases pressure decreases . The ink in the refil of pen is filled at atmospheric pressure . When air plane fly up the atmospheric pressure on the ink decreases and hence ink comes out on cloth .Hence , when the air plane fly up , it is not right to keep a fountain pen in a pocket .
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KUMAR PRAKASHAN-MECHANICAL PROPERTIES OF FLUIDS -SECTION -C (Objective Questions) (VSQs)
  1. Why does food cook faster in a pressure cooker ?

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  2. Explain that you can't make a decent cup of tea up on a mountain ?

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  3. When air plane fly at higher altitude it is not right to keep a founta...

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  4. Mountaineers suffer from nose bleeding (nostril ) at higher altitudes.

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  5. It is difficult to heal wound on mountain.

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  6. Straws are used to take soft drinks . Why ?

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  7. Explain why are water storage dam walls thicker at the bottom.

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  8. Why does an air bubble form in water grow in size from bottom when it ...

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  9. Why is mercury used in a barometer ?

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  10. What are difficulties arised by using water in a barometer instead of ...

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  11. What does it mean when a height of a barometer is falling ?

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  12. What does it mean when a height of a barometer is rising ?

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  13. A barometer kept in a elevator accelerating upwards with acceleration ...

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  14. A barometer kept in an elevator accelerating downwards with accelerat...

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  15. What is buoyant force ?

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  16. Why does a ship made of iron float while a piece of iron sinks in wate...

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  17. A person is sitting in aboat floating in a lake . This person fills a ...

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  18. A container of liquid is free fall without flyout of liquid is this co...

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  19. When two corks , one small and one big are taken into a vessel filled ...

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  20. Why is it easier to swim in sea water than in river water ?

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