Home
Class 11
PHYSICS
Assertion: When a body dropped from a he...

Assertion: When a body dropped from a height explodes in mid air, its center of mass keeps moving in vertically downward directions.
Reason: Explosion occurs under internal forces only. External force is zero.

A

If both assertion and reason are true and the reason is the correct explanation of the assertion.

B

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

C

If assertion is true but reason is false.

D

If the assertion and reason both are false.

Text Solution

Verified by Experts

The correct Answer is:
A
Explosion is due to internal forces. As no external force is involved, the vertical downward motion of centre of mass is not affected.
Promotional Banner

Topper's Solved these Questions

  • ROTATIONAL MOTION

    ERRORLESS|Exercise NCERT BASED QUESTIONS (Torque and Couple)|27 Videos

  • NEWTON'S LAWS OF MOTION

    ERRORLESS|Exercise ASSERTION & REASON |18 Videos

  • SIMPLE HARMONIC MOTION

    ERRORLESS|Exercise Assertion & Reason|15 Videos

Similar Questions

Explore conceptually related problems

Assertion : When a bicycle is in motion, the force of friction exerted by the ground on the two wheels is always in forward direction. Reason : The frictional force acts only when the bodies are in contact

Assertion: If a projectile explodes in mid air, then no external force acts on the projectile during explosions. Reason: Center of mass in this case follows the same path.

Assertion :- A ball is thrown from the edge of a very high clif. No matter what the angle at which it is thrown , due to air resistance, the ball will eventually end up moving vertically downward. Reason :- In horizontal direction there is a component of retarding force of air resistance alone.

Assertion: When the body is dropped or thrown horizontally form the same height, it would reach the ground at the same time. Reason: Horizontal velocity has no effect on the vertical direction.

A ball starts falling under the effect of gravitational force from a height of 45m. When it reaches a height of 25 m. When it reaches a height of 25 m it explodes into two pieces of mass ratio 1:2 . There is no change in the vertical motion of the piece after the explosion but they acquire horizontal velocity. If the heavier piece gains a horizontal velocity of 10ms^(-1) , then the distance between the two pieces when both of them strike the ground is

Assertion : A body can be at rest even when it is under the action of may number of external forces Reason : Because vector sum of the all external forces is zero .

Assertion: A projectile gets exploded at its highest point. All the piece get only horizontal velocities. Reason: The weight of the projectile is the external force for projectile.

A projectile of mass mis fired with an initial velocity v_(0) at an angle 0 to the horizontal. At its highest point, it explodes into two fragments of equal mass. One of the fragments falls vertically with zero initial speed. Since the only external force acting on the system is gravitational, the motion of centre of mass of the_ system (the fragments) follows the same parabolic path as the projectile would have followed if there had been no explosion. Force of explosion is internal, it cannot change the trajectory of the system.

ERRORLESS-ROTATIONAL MOTION-Assertion & Reason
  1. Statement-1 : The centre of mass of a proton and an electron, released...

    Text Solution

    |

  2. Statement-1 : The position of centre of mass of a body does not depend...

    Text Solution

    |

  3. Assertion : A shell at rest, explodes. The centre of mass of fragments...

    Text Solution

    |

  4. Assertion: A judo fighter in order to throw his opponent onto the matt...

    Text Solution

    |

  5. Assertion: The centre mass of an electron and proton, when released mo...

    Text Solution

    |

  6. Assertion : At the centre of earth, a body has centre of mass , but no...

    Text Solution

    |

  7. Assertion: When a body dropped from a height explodes in mid air, its ...

    Text Solution

    |

  8. Statement -1: It is harder to open and shut the door if we apply force...

    Text Solution

    |

  9. Statement-1 : Moment of inertia of a particle is same, whatever be the...

    Text Solution

    |

  10. Assertion : Inertia and moment of inertia are same quantities. Reaso...

    Text Solution

    |

  11. If earth shrink (without change in mass) to half it's present size. Le...

    Text Solution

    |

  12. Statement -1: Torque due to force is maximum when angle between vec r ...

    Text Solution

    |

  13. Statement-1 : Radius of gyration of a body is a constant quantity. ...

    Text Solution

    |

  14. Assertion: A ladder is more apt to slip, when you are high up on it th...

    Text Solution

    |

  15. Statement -1 : Torque is equal to rate of change of angular momentum ....

    Text Solution

    |

  16. Assertion : The speed of a whirl wind in a tornado is alarmigly high. ...

    Text Solution

    |

  17. Assertion : The velocity of a body at the bottom of an inclined plane ...

    Text Solution

    |

  18. Assertion : In rolling, all points of a rigid body have the same linea...

    Text Solution

    |

  19. Assertion : A wheel moving down a perfectly frictionless inclined plan...

    Text Solution

    |

  20. Assertion : The total kinetic energy of a rolling solid sphere is the ...

    Text Solution

    |