What will be needed in order to restore the balance if necessary?

scale1kgiceYou have a beam balance, the kind of scales that tips from one side to the other, depending on the weight on each side. On the left side lies a kilogram of ice. On the right side lies the standard kilogram. The pans are in balance.
After a while all the ice melted.
Does the balance tip to the right, to the left, or does it remain unchanged?
What will be needed in order to restore the balance if necessary?

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The surface energy of a liquid drop

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The surface energy of a liquid drop is u. It is sprayed into 1000 identical drops. What will be the total surface energy?

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A fast moving train cross a person standing near a railway track

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When a fast moving train cross a person standing near a railway track, the person has a tendency to fall towards the train. This is because

a) a gravitational force
b) of dizziness related to vestibular system dysfunction
c) vibrations of air created by the train
d) a fast moving train creates large velocity of air between the person and the train
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A yacht drops anchor

yacht

A yacht drops its anchor overboard. What happens to the water
level?

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A ball fell into a vessel

BallVessel A wooden ball fell into a high cylindrical vessel. The diameter of the vessel and the diameter of the ball is 5 cm and 4 cm respectively. Can you get the ball without touching the vessel?

 

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Why do golf balls need dimples?

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The stream of water.

faucet2Why does the stream of water flowing from a faucet often get more narrow as the water falls?

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