Home
Class 11
PHYSICS
Assertion: Friction opposes relative mot...

Assertion: Friction opposes relative motion and thereby dissipates power in the form of heat.
Reason: Friction is always an undesirable force.

A

If both assertion and reason are true and reason is not the correct explaination of assertion.

B

If both assertion and reason are true but reason is not the correct explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
C
We consider friction as an undesirable force sometimes, not always. In many situation, like in a machine with different moving parts, friction does have a negative role. It opposes relative motion and thereby dissipates power in the from of heat etc.
Promotional Banner

Topper's Solved these Questions

  • NEWTONS LAWS OF MOTION

    A2Z|Exercise AIIMS Questions|26 Videos

  • MOTION IN TWO DIMENSION

    A2Z|Exercise Chapter Test|29 Videos

  • OSCILLATION AND SIMPLE HARMONIC MOTION

    A2Z|Exercise Chapter Test|29 Videos

Similar Questions

Explore conceptually related problems

Does friction always oppose the motion?

Assertion : Eddy currents heat up the core and dissipate electrical energy in the form of heat. Reason : Eddy currents are always undesirable.

These questions consists of two statements each printed as Assertion and Reason. While answering these question you are required to choose any one of the following four responses Assertion: Friction always opposes the relative motion of two bodies. Reason: Without friction also, one can move on a smooth surface.

Assertion: Frictional force is the component of contact force parallel to the surface. Reason: Friction force always opposes the motion of a body.

Frictional force always opposes motion of a body.

In moving machine with different moving parts friction .....X..... the relative motion, and power dissipated in the form of ...Y....Here X and Y refers to

Assertion : Friction always opposes the motion. Reason : Whenever one surface moves or tries to move over another surface, the force of friction starts acting on the surfaces.

Choose the correct options – (1) Friction always opposes the motion (2) Friction may opposes the motion (3) If the applied force is increased the force of static friction remains constant. (4) If the applied force is increased the force of static friction also increases upto limiting friction.

A2Z-NEWTONS LAWS OF MOTION-Chapter Test
  1. A person holds a spring balance with a mass m hanging from it goes up ...

    Text Solution

    |

  2. Two equal masses are kept on the pans of a simple balance in a lift ac...

    Text Solution

    |

  3. The force required to just move a body up an inclined plane is double ...

    Text Solution

    |

  4. A mass of 4kg is suspended by a rope of length 4m from a ceiling. A fo...

    Text Solution

    |

  5. In the figure, a block of weight 60N is placed on a rough surface. Th...

    Text Solution

    |

  6. A rocket is going upward with acceleration motion. A man sitting in it...

    Text Solution

    |

  7. A body is moving under the action of two force vec(F(1))=2hati-5hatj ,...

    Text Solution

    |

  8. A body of mass 10kg is acted upon by two perpendicular force, 6N . The...

    Text Solution

    |

  9. A monkey of mass 20kg is holding a vertical rope. The rope will not br...

    Text Solution

    |

  10. A body mass 2kg has an initial velocity of 3 metre//sec along OE and i...

    Text Solution

    |

  11. A force of 100N need to be applied parallel to a smooth inclined plane...

    Text Solution

    |

  12. A plumb bob is hung from the ceiling of a train compartment. The train...

    Text Solution

    |

  13. A man is raising himself and the crate on which he stands with an acce...

    Text Solution

    |

  14. A balloon of mass M is descending at a constant acceleration alpha. Wh...

    Text Solution

    |

  15. A string of length L is fixed at one end and carries a mass M at the o...

    Text Solution

    |

  16. Two block of masses M(1) and M(2) are connected with a string passing...

    Text Solution

    |

  17. An inclined plane makes an angle 30^(@) with the horizontal. A groove ...

    Text Solution

    |

  18. Assertion: Force is always in the direction of motion. Reason: In ev...

    Text Solution

    |

  19. Assertion: Force on a body A by body B is equal and opposite to the fo...

    Text Solution

    |

  20. Assertion: Friction opposes relative motion and thereby dissipates pow...

    Text Solution

    |