Home
Class 12
PHYSICS
An object is dropped from a height h fro...

An object is dropped from a height h from the ground .Every time it hits the ground it looses 50% of its kinetic energy.The total distance covered as `t to oo` is:

A

3h

B

`oo`

C

`(5)/(3)h`

D

`(8)/(3)h`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we need to analyze the motion of the object dropped from height \( h \) and how its kinetic energy changes with each bounce. ### Step-by-Step Solution: 1. **Initial Drop**: - The object is dropped from a height \( h \). - The potential energy at height \( h \) is converted into kinetic energy just before it hits the ground. - The potential energy (PE) at height \( h \) is given by: \[ PE = mgh \] - When it hits the ground, all this potential energy converts to kinetic energy (KE): \[ KE = \frac{1}{2} mv^2 = mgh \] - From this, we can find the velocity just before impact: \[ v = \sqrt{2gh} \] 2. **First Impact**: - Upon hitting the ground, the object loses 50% of its kinetic energy. - Therefore, the kinetic energy after the first impact is: \[ KE' = \frac{1}{2} KE = \frac{1}{2} (mgh) = \frac{1}{2} mgh \] 3. **Height Reached After First Bounce**: - The remaining kinetic energy is converted back into potential energy as it rises. - The potential energy at the new height \( h_1 \) is: \[ mgh_1 = \frac{1}{2} mgh \] - Solving for \( h_1 \): \[ h_1 = \frac{1}{2} h \] 4. **Subsequent Bounces**: - After reaching height \( h_1 \), the object again loses 50% of its kinetic energy when it hits the ground. - The kinetic energy after the second impact becomes: \[ KE'' = \frac{1}{2} KE' = \frac{1}{4} mgh \] - The height reached after the second bounce \( h_2 \) is: \[ mgh_2 = \frac{1}{4} mgh \implies h_2 = \frac{1}{4} h \] 5. **Continuing the Pattern**: - This pattern continues, where the height after each bounce is halved: - \( h_3 = \frac{1}{8} h \) - \( h_4 = \frac{1}{16} h \) - And so on... 6. **Total Distance Covered**: - The total distance covered by the object can be calculated as: \[ \text{Total Distance} = h + 2\left(h_1 + h_2 + h_3 + \ldots\right) \] - The heights \( h_1, h_2, h_3, \ldots \) form a geometric series: \[ h_1 + h_2 + h_3 + \ldots = \frac{h}{2} + \frac{h}{4} + \frac{h}{8} + \ldots \] - The first term \( a = \frac{h}{2} \) and the common ratio \( r = \frac{1}{2} \). - The sum of an infinite geometric series is given by: \[ S = \frac{a}{1 - r} = \frac{\frac{h}{2}}{1 - \frac{1}{2}} = \frac{\frac{h}{2}}{\frac{1}{2}} = h \] 7. **Final Calculation**: - Therefore, the total distance covered is: \[ \text{Total Distance} = h + 2S = h + 2h = 3h \] ### Conclusion: The total distance covered by the object as \( t \) tends to infinity is \( 3h \).

To solve the problem step by step, we need to analyze the motion of the object dropped from height \( h \) and how its kinetic energy changes with each bounce. ### Step-by-Step Solution: 1. **Initial Drop**: - The object is dropped from a height \( h \). - The potential energy at height \( h \) is converted into kinetic energy just before it hits the ground. - The potential energy (PE) at height \( h \) is given by: ...
Promotional Banner

Topper's Solved these Questions

  • CONCEPT BUILDER

    DISHA PUBLICATION|Exercise Exercise-1 Concept Builder (topicwise)|34 Videos
  • CONCEPT BUILDER

    DISHA PUBLICATION|Exercise Exercise-1 Concept Builder (Topic 2:Energy)|15 Videos
  • COMMUNICATION SYSTEM

    DISHA PUBLICATION|Exercise EXERCISE-2 : Concept Applicator|30 Videos
  • CURRENT ELECTRICITY

    DISHA PUBLICATION|Exercise EXERCISE-2 Concept Applicator|23 Videos

Similar Questions

Explore conceptually related problems

A ball is dropped from a height 64 m above the ground and every time it hits the ground it rises to a height equal to half of the previous. What is the height attained after it hits the ground for the 16^(th) time?

A ball is dropped from a height 64m above the ground and every time it hits the ground it rises to a height equal to half of the previous height.The height attained after it hits the ground for the 16h time is

A ball initally at rest is dropped from a height of 10 m . In strinking the ground , it loses 20 % of its kinetic energy . Calculate the height to which it bounces . Where does the lost kinetic energy go ?

An object is dropped from a height h . Then the distance travelled in times t,2t,3t are in the ratio.

A 500 g ball is released from a height of 4m. Each time it makes contact with the ground, it loses 25% of its kinetic energy. Find the kinetic energy it possess just after the 3^(rd) hit

A rock is dropped from rest from a height h above the ground. It falls and hits the ground with a speed of 11 m/s. From what height should the rock be dropped so that its speed on hitting the ground is 22 m/s ? Neglect air resistance.

An object is released from a certain height above the ground. Just at the time it touches the ground, it will possesses "_________" .

A golf ball is dropped form a height of 80 m. Each time the ball hits the ground, it rebound to 1/3 of the height through which it has fallen. Then total distance travelled by the ball is

DISHA PUBLICATION-CONCEPT BUILDER-Exercise-2 Concept Applicator
  1. An object is dropped from a height h from the ground .Every time it hi...

    Text Solution

    |

  2. A small block of mass m is kept on a rough inclined surface of inclina...

    Text Solution

    |

  3. The potential energy of a 1 kg particle free to move along the x- axis...

    Text Solution

    |

  4. A particle initially at rest on a frictionless horizontal surface, is ...

    Text Solution

    |

  5. A moving body with a mass m(1) strikes a stationary body of mass m(2)....

    Text Solution

    |

  6. A toy gun a spring of force constant k. When changed before being trig...

    Text Solution

    |

  7. A block of mass 5.0 kg is suspended from the end of a vertical spring ...

    Text Solution

    |

  8. Water is drawn from a well in a 5kg drum of capacity 55L by two ropes ...

    Text Solution

    |

  9. A 2 kg block slides on a horizontal floor with a speed of 4 m/s. It st...

    Text Solution

    |

  10. A body of mass m kg is ascending on a smooth inclined plane of inclina...

    Text Solution

    |

  11. A projectile moving vertically upwards with a velocity of 200 ms^(-1) ...

    Text Solution

    |

  12. A point particle of mas 0.5kg is moving along the x-axis under a force...

    Text Solution

    |

  13. Two blocks A and B of masses in and 2m respectively placed on a smooth...

    Text Solution

    |

  14. A car of weight W is on an inclined road that rises by 100 m over a di...

    Text Solution

    |

  15. A horse drinks water from a cunical container of side 1m .The level of...

    Text Solution

    |

  16. A wind - powered generator convets and energy into electrical energy ...

    Text Solution

    |

  17. A vertical spring with force constant k is fixed on a table. A ball of...

    Text Solution

    |

  18. A block of mss m rests on a rough horizontal surface (Coefficient of f...

    Text Solution

    |

  19. In the figure shown ,a particle of mass m is released from the positio...

    Text Solution

    |

  20. Figure shows a block of mass m,kept on a smooth horizontal plane and a...

    Text Solution

    |

  21. Consider elastic collision of a particle of mass m moving with a veloc...

    Text Solution

    |