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General Knowledge :: Physics

  1. A hydrogen balloon floats up because of

  2. A.

     Air pressure decreases with decrease in height

    B.

     Air pressure decreases with decrease in weight

    C.

     Weight of the balloon is less than the weight of air displaced by it.

    D.

     The pressure inside the balloon is more than the pressure outside it

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  3. A boat will submerge when it displaces water equal to its own:

  4. A.

     Volume

    B.

     Weight

    C.

     Surface area

    D.

     Density

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  5. What is the principle of a ''Life Jacket"?

  6. A.

     It provides oxygen to a drowning person

    B.

     It increases the volume of the person to keep him afloat

    C.

     It decreases the volume of the person to keep him afloat

    D.

     The person can sit on it like a raft

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  7. When a piece of stone is immersed in water, it displaces water of equal

  8. A.

     Density

    B.

     Specific gravity

    C.

     Mass

    D.

     Volume

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  9. It is easier for a man to swim in sea water, than in river water because

  10. A.

     The density of sea water is lesser than the density of river water

    B.

     The density of sea water is more than the density of river water

    C.

     The sea is-deeper than the river

    D.

     The sea is wider than the river

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  11. A piece of wood is held under water. The upthrust on it will be:

  12. A.

     Equal to the weight of the wood

    B.

     Less than weight of the wood

    C.

     More than weight of the wood

    D.

     Zero

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  13. An egg sinks in soft water but floats in a concentrated solution of salt because

  14. A.

     Egg absorbs salt from the solution and expands

    B.

     Albumin dissolves in salt solution and egg becomes lighter

    C.

     The density of salt solution exceeds the density of eggs

    D.

     Water has high surface tension

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  15. When a ship enters the sea from a river what will be the effect?

  16. A.

     It lowers

    B.

     It sways

    C.

     It rises a little

    D.

     It jolts

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  17. Two identical solid pieces, one of gold and other of silver, when immersed completely in water exhibit equal weights. When weighed in air (given that density of gold is greater than that of silver)

  18. A.

     The gold piece will weigh more

    B.

     The silver piece will weigh more

    C.

     Both silver and gold pieces weigh equal

    D.

     Weighing will depend on their masses

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  19. When a body is immersed in a liquid, the force acting on it is

  20. A.

     Upthrust

    B.

     Weight

    C.

     Mass

    D.

     Both (A) and (B)

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