Compare rolling friction and sliding friction. How are they different in terms of contact surfaces, motion, and forces involved? Explain with examples.

  • Rolling friction occurs when an object rolls over a surface, such as a wheel or a ball. It involves less resistance compared to sliding friction because the contact area is smaller.
  • Sliding friction occurs when an object slides over a surface, and the frictional force is higher due to the larger contact area and interlocking of surface irregularities.

Differences:

  • Contact surface: Rolling friction has a smaller contact area than sliding friction.
  • Motion: In rolling friction, the object rotates, while in sliding friction, the object moves across the surface without rotation.
  • Forces involved: Rolling friction typically generates less resistance than sliding friction because of the reduced surface contact.

Examples:

  • Rolling friction: A ball rolling on the ground.
  • Sliding friction: A box being pushed across the floor.

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