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प्रश्न
List three ways of reducing friction.
उत्तर
Ways to reduce friction:
- Providing ball bearings or wheels between the moving parts of the machine or vehicles reduces friction and allow smooth movement as rolling friction is less than sliding friction.
- Oiling or lubricating (with graphite or grease) the moving parts of a machine reduces friction. Fine powder like talcum powder also works as a lubricant to reduce friction.
- Polishing the rough surface reduces friction offered by it.
- Streamlining (giving special shape to experience minimum drag) the bodies of aeroplanes, cars, boats, and ships help reduce drag (fluid friction) while travelling through air or water.
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संबंधित प्रश्न
Explain why sportsmen use shoes with spikes.
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Answer the following in short.
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Answer the following in short.
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Complete the analogy.
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Analogy
Objects placed at rest on earth: ______:: Bodies slide over the surface on other body: ______.
