Home
Class 12
PHYSICS
Assertion: A body of weight 10N (W) is a...

Assertion: A body of weight 10N (W) is at rest on an inclined plane `(mu=sqrt(3)/(2))` making an angle of `30^(@)` with the horizontal. The force of friction acting on it is 5N
Reason: In above situation, the limiting force of friction is given by `f_("limitting")=mu W cos theta=7.5N`.

A

If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.

B

If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.

C

If Assertion is Trie but the Reason is False.

D

If both Assertion `&` Reason are false

Text Solution

Verified by Experts

The correct Answer is:
B
`f=mg sin theta=10xx(1)/(2)=5N`
`f_("max")=mu mg cos theta=7.5N`
NO explanation for friction `lt f` (limmiting)
Promotional Banner

Topper's Solved these Questions

  • NEWTONS LAWS OF MOTION

    ALLEN |Exercise EXERCISE-II|112 Videos

  • NEWTON'S LAWS OF MOTION & FRICTION

    ALLEN |Exercise EXERCISE (JA)|4 Videos

  • RACE

    ALLEN |Exercise Basic Maths (Wave Motion & Dopplers Effect) (Stationary waves & doppler effect, beats)|25 Videos

Similar Questions

Explore conceptually related problems

A body of mass 5xx10^(-3) kg is launched upon a rough inclined plane making an angle of 30^(@) with the horizontal. Obtain the coefficient of friction between the body and the plane if the time of ascent is half of the time of descent.

A block rests on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block ((in kg) is .......... (Take g = 10 m//s^(2) )

A block is moving on an inclined plane making an angle 45^@ with the horizontal and the coefficient of friction is mu . The force required to just push it up the inclined plane is 3 times the force required to just prevent it from sliding down. If we define N=10mu , then N is

A block is released on the slant face of a wedge of equal mass placed on a horizontal floor. The slant face of the wedge makes an angle of 45^(@) with the floor. Coefficient of friction between all surfaces in contact is the same. Different value/ range of coefficient of friction is given in column I and corresponding consequences in column II and III (wedge is fress to move) {:(,"Column-I",,"Column-II",,"Column-III",),((I),mu=0,(i),"Work done by friction on block and wedge is negative (on each)",(P),"Centre of mass of system (block+wedge) moves rightward and downward",),((II),mu gt 1,(ii),"Work done by friction on block is negative but on wedge it is zero",(Q),"Centre of mass of system (block+wedge) moves leftward and downward",),((III),sqrt(5)-2 lt mu lt 1,(iii),"Work done by friction on block and wedge is zero (on each)",(R ),"Centre of mass of system (block+wedge) remains at rest",),((IV),mu lt sqrt(5) - 2,(iv),"Friction between the block and wedge is static and between the wedge and ground it is kinetic in nature.",(S),"Centre of mass of system (block+wedge) moves vertically downward",):} Which of the following options is the correct representation of the case that the wedge remains motionless and the block slides down

The figure shows a horizontal force vecF acting on a block of mass M on an inclined plane (angle theta ). What is the normal reaction N on the block?

A block of mass 2kg is pushed down an inclined plane of angle 37^(@) above horizontal with a force parallel to inclined plane. The coefficient of friction is (3)/(4). The block moves 10 m in 2 seconds starting form rest. The magnitude of the force is

Block A of weight 100 N rests on a frictionless inclined plane of slope angle 30^(@) . A flexible cord attached to A passes over a frictionless pulley and is connected to block B of weight w. Find the weight w for which the system is in equilibrium

A rocket is fired vertically from the earth with an acceleration of 2g, where g is the gravitational acceleration. On an inclined plane inside the tocket, making an angle theta with the horizontal, a point object of mass m is kept, the minimum coefficient of friction mu_(min) between the mass and the inclined suface such that the mass does not move is:

A weight W rests on a rough horizontal plane,If the angle of friction is theta ,the least force that can move the body along the plane will be

A block rest on a rough inclined plane as shown in fig. A horizontal force F is applied to it (a) Find out the force of reaction, (b) Can the force of friction be zero if yes when? And (c) Assuming that fricition is not zero find its magnitude and direction of its limiting value.

ALLEN -NEWTONS LAWS OF MOTION-EXERCISE-III
  1. Assertion: Frictional force is the component of contact force parallel...

    Text Solution

    |

  2. Assertion: Newton's first law can be derived from the second law. Re...

    Text Solution

    |

  3. These questions consists of two statements each printed as Assertion a...

    Text Solution

    |

  4. Assertion: Pseudo force is an imaginary force which is recongnised on...

    Text Solution

    |

  5. Assertion: A table cloth can be pulled from a table without dislodding...

    Text Solution

    |

  6. Assertion: Friction is a self-adjusting force. Reason: A block on th...

    Text Solution

    |

  7. Assertion: The apparent weight of a person standing in a lift which mo...

    Text Solution

    |

  8. Assertion: A body of weight 10N (W) is at rest on an inclined plane (m...

    Text Solution

    |

  9. Assertion: When a force vecF attempts to slide a body along a surface,...

    Text Solution

    |

  10. Assertion: Mass is a property of one object alone, whereas weight resu...

    Text Solution

    |

  11. Assertion: When brakes are applied on a wet road, a car is likely to s...

    Text Solution

    |

  12. Assertion : The force of tension on a body always act away from the bo...

    Text Solution

    |

  13. Assertion: It is difficult to move a heavy box by sliding whereas it b...

    Text Solution

    |

  14. Assertion: Every mutual intraction between two bodies always follow th...

    Text Solution

    |

  15. Assertion: Static slides down an inclined plane if the angle of fricti...

    Text Solution

    |

  16. Assertion: Magnitude of the contact force is always greater than the m...

    Text Solution

    |

  17. Assertion: When a person walks on a rough surface, the frictional forc...

    Text Solution

    |

  18. Assertion: Newton's second law of motion gives the measurement of forc...

    Text Solution

    |

  19. Assertion: Pulling a lawn roller is easier than pushing it. Reason:P...

    Text Solution

    |

  20. Assertion: A man who falls from aheight on a cement floor receive more...

    Text Solution

    |