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प्रश्न
Give examples to show that friction is both a friend and a foe.
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उत्तर
Examples to show that friction is a friend:
- Friction enables us to grip and catch various objects.
- It allows us to walk pleasantly on the surface.
- It helps reduce the speed of moving items.
- It will enable us to write on paper or blackboards.
- Friction prevents objects from moving from their original positions.
Examples to show that friction is a foe:
- Friction wears and tears items.
- It damages machine parts.
- Machines and tools require constant maintenance, which wastes a lot of money.
- It slows down moving objects, requiring more significant force.
- It prohibits the free movement of items.
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| Column I | Column II | |
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