Home
Class 12
PHYSICS
Frictional force increases when surfaces...

Frictional force increases when surfaces in contact are made very very smooth. This is because

A

of molecular force

B

decrease in surface area

C

decrease in irregularities

D

increase in area

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • FRICTION

    MBD PUBLICATION|Exercise QUISTION BANK|72 Videos
  • ELECTROMAGNETIC WAVES

    MBD PUBLICATION|Exercise QUESTION BANK|180 Videos
  • GRAVITATION

    MBD PUBLICATION|Exercise QUESTION BANK|219 Videos

Similar Questions

Explore conceptually related problems

The frictional force between two. surfaces is independent of

Why the coefficient of friction between two surfaces in contact varies directly with the normal reaction ?

Coefficient of friction between two surfaces in contact is always less than_____.

Explain the following : (i) The paramagnetic character in 3d-transition series increases upto Cr and then decreases. (ii) Transition metals are very good catalyst. (iii) Transition metals form a large number of interstitial compounds.

State whether the following assertion is true or false : When a person walks on a rough surface, the frictional force exerted by the surface on the person is opposite to the direction of his motion.

Atomic weights of practically all the elements are very nearly whole numbers and not always whole numbers. This is because :

The melting points of most of the solid substances increase with an increase of pressure acting on them. However, ice melts at a temperature lower than its usual meiting point, when the pressure increases. This is because:

When the temperature increases the angle of contact of a liquid ____.

Force of friction arises due to_____of the irregularities of the two surfaces in contact.

MBD PUBLICATION-FRICTION-QUISTION BANK
  1. Frictional force increases when surfaces in contact are made very very...

    Text Solution

    |

  2. Is it reasonable to expect the coefficient of friction to exceed unity...

    Text Solution

    |

  3. It is known that polishing a surface beyond a certain limit increases ...

    Text Solution

    |

  4. Why do we slip on a muddy road ?

    Text Solution

    |

  5. State whether the following assertion is true or false : When a person...

    Text Solution

    |

  6. Is a large brake on a bicycle wheel more effective than a small one ?

    Text Solution

    |

  7. Why are vehicles provided with wheels and- ball bearing ?

    Text Solution

    |

  8. Comment on the statement ‘friction is necessary evil’.

    Text Solution

    |

  9. It is easier to than push.

    Text Solution

    |

  10. How does a lubricant help in decreasing friction ?

    Text Solution

    |

  11. To slide a heavy box, we generally left it a bit to place a metallic p...

    Text Solution

    |

  12. Why has a horse to pull a cart harder during the first few steps of hi...

    Text Solution

    |

  13. How do we save petrol when the tyres of the motor cycle are fully infl...

    Text Solution

    |

  14. Write down the dimensional formula of force of friction

    Text Solution

    |

  15. Write down the mathematical expression for coefficient of static frict...

    Text Solution

    |

  16. Write down the mathematical expression for coefficient of kinetic fric...

    Text Solution

    |

  17. Write down the mathematical expression for coefficient of static frict...

    Text Solution

    |

  18. What is the slope of the graph attained by plotting of dynamic frictio...

    Text Solution

    |

  19. What is static friction ?

    Text Solution

    |

  20. What is kinetic friction ?

    Text Solution

    |

  21. Discuss the statement “friction is a necessary evil”.

    Text Solution

    |