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प्रश्न
Answer the following in short.
What do you understand by normal force?
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उत्तर
A force exerted by a surface to support the weight of a body in contact with it is called the normal force. It is always perpendicular (right angles) to the surface. For example, when a book is kept on a table, the table exerts a normal force which acts upward on the book to support its weight.
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संबंधित प्रश्न
Give examples to show that friction is both a friend and a foe.
The eraser gets smaller and smaller as you use it more and more. Explain the reason.
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Fill in the blank.
Rolling friction offers ............. resistance than sliding friction.
Fill in the blank.
Weight remaining the same, friction is independent of ............. of surface in contact.
Tick the most appropriate answer.
Friction produces
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Friction depends upon the ............... of an object.
Answer the following in a word or two or in a sentence.
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