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Give examples to show that friction is both a friend and a foe. - Science

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Question

Give examples to show that friction is both a friend and a foe.

Answer in Brief

Solution

Examples to show that friction is a friend:

  1. Friction enables us to grip and catch various objects.
  2. It allows us to walk pleasantly on the surface.
  3. It helps reduce the speed of moving items.
  4. It will enable us to write on paper or blackboards.
  5. Friction prevents objects from moving from their original positions.

Examples to show that friction is a foe:

  1. Friction wears and tears items.
  2. It damages machine parts.
  3. Machines and tools require constant maintenance, which wastes a lot of money.
  4. It slows down moving objects, requiring more significant force.
  5. It prohibits the free movement of items.
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Force of Friction
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Chapter 12: Friction - Exercises [Page 155]

APPEARS IN

NCERT Science [English] Class 8
Chapter 12 Friction
Exercises | Q 9 | Page 155

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