Define force of friction. What causes friction? What are the advantages and disadvantages of friction? Explain with examples. How can friction be reduced?

Friction is the resistive force that opposes the relative motion between two surfaces in contact.

Causes of friction: Friction arises due to the irregularities and microscopic asperities on the surfaces of the materials in contact. These microscopic bumps and ridges interlock, creating resistance to motion.

Advantages of friction:

  • It allows us to walk without slipping.
  • It enables vehicles to grip the road, preventing skidding.
  • It allows us to hold onto objects, such as when we grip a pen or use brakes in vehicles.

Disadvantages of friction:

  • It causes wear and tear on machinery parts, reducing their lifespan.
  • It generates heat, leading to energy loss, such as in engines and brakes.

How to reduce friction:

  • By lubricating surfaces (e.g., using oil or grease).
  • By making surfaces smoother.
  • Using ball bearings or rollers to reduce direct contact.

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  16. Q6. Look at the measurement of vernier calipers:
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