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प्रश्न
Explain how friction can be minimized.
उत्तर
- Using lubricants:
- A substance, which reduces the frictional force, is called a lubricant. Example: Grease, coconut oil, graphite, castor oil, etc.
- The lubricants fill up the gaps in the irregular surfaces between the bodies in contact. This provides a smooth layer thus preventing direct contact between their rough surfaces.
- Using ball bearing:
Since the rolling friction is smaller than sliding friction, sliding is replaced by rolling with the usage of ball bearings. We can see lead shots in the bearing of a cycle hub.
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