Home
Class 11
PHYSICS
A lift starts from rest. Its acceleratio...

A lift starts from rest. Its acceleration is plotted against time. When it comes to rest its height above its starting point is

A

`20 m`

B

`64 m`

C

`32 m`

D

`36 m`

Text Solution

Verified by Experts

The correct Answer is:
B
At 4s
`u=at=8m//s`
`s_1=1/2at^2=1/2xx2xx4^2=16m`
From 4s to 8s
`a=0, v=constant=8m//s`
`:. s_2=vt=(8)(4)=32m`
From 8s to 12s
`s_3=s_1=16m`
`:. s_(Total)=s_1+s_2+s_3=64m`
Promotional Banner

Topper's Solved these Questions

  • KINEMATICS

    DC PANDEY ENGLISH|Exercise Subjective|50 Videos

  • KINEMATICS

    DC PANDEY ENGLISH|Exercise More Than One Correct|6 Videos

  • KINEMATICS

    DC PANDEY ENGLISH|Exercise Assertion And Reason|12 Videos

  • GRAVITATION

    DC PANDEY ENGLISH|Exercise (C) Chapter Exercises|45 Videos

  • KINEMATICS 1

    DC PANDEY ENGLISH|Exercise INTEGER_TYPE|15 Videos

Similar Questions

Explore conceptually related problems

A particle starts from rest. Its acceleration is varying with time as shown in the figure. When the particle comes to rest, its distance from its starting point is

A particle start from rest, with uniform acceleration at time t , choose the correct option

A lift a mass 1200 kg is raised from rest by a cable with a tension 1350 kg f . After same time the tension drops to 1000 kg f and the lift comes to rest at a height of 25 m above its intial point (1 kg - f = 9.8 N) What is the greatest speed of lift?

A lift a mass 1200 kg is raised from rest by a cable with a tension 1350 kg f . After same time the tension drops to 1000 kg f and the lift comes to rest at a height of 25 m above its intial point (1 kg - f = 9.8 N) What is the height at which the tension changes ?

A particle starts from rest. Its acceleration at time t=0 is 5 m//s^(2) which varies with time as shown in the figure. The maximum speed of the particle will be

A lift starts from rest with a constant upward acceleration It moves 1.5 m in the first 0.4 A person standing in the lift holds a packet of 2 kg by a string Calculate the tension in the string during the motion .

Two electrons starting from rest are accelerated by equal potential difference.

A particle starting from rest. Its acceleration (a) versus time (t) is as shown in the figure. The maximum speed of the particle will be.

A particle starting from rest. Its acceleration (a) versus time (t) is as shown in the figure. The maximum speed of the particle will be.

A body starts from rest and then moves with uniform acceleration. Then.

DC PANDEY ENGLISH-KINEMATICS-Objective
  1. A ball is released from the top of a tower of height h metre. It takes...

    Text Solution

    |

  2. An ant is at a corner of a cubical room of side a. The ant can move wi...

    Text Solution

    |

  3. A lift starts from rest. Its acceleration is plotted against time. Whe...

    Text Solution

    |

  4. A lift performs the first part of its ascent with uniform acceleration...

    Text Solution

    |

  5. Two objects are moving along the same straight line. They cross a poin...

    Text Solution

    |

  6. A cart is moving horizontally along a straight line with constant spee...

    Text Solution

    |

  7. The figure shows velocity-time graph of a particle moving along a stra...

    Text Solution

    |

  8. A ball is thrown vertically upwards from the ground and a student gazi...

    Text Solution

    |

  9. A body starts moving with a velocity v0 = 10 ms^-1. It experiences a r...

    Text Solution

    |

  10. Two trains are moving with velocities v1 = 10 ms^-1 and v2 = 20 ms^-1 ...

    Text Solution

    |

  11. Two balls of equal masses are thrown upwards, along the same vertical ...

    Text Solution

    |

  12. A particle is projected vertically upwards and reaches the maximum hei...

    Text Solution

    |

  13. A particle moves along the curve y = x^2 /2. Here x varies with time a...

    Text Solution

    |

  14. If the displacement of a particle varies with time as sqrt x = t+ 3

    Text Solution

    |

  15. The graph describes an airplane's acceleration during its take-off run...

    Text Solution

    |

  16. A particle moving in a straight line has velocity-displacement equatio...

    Text Solution

    |

  17. A particle is thrown upwards from ground. It experiences a constant re...

    Text Solution

    |

  18. A body of mass 10 kg is being acted upon by a force 3t^2 and an opposi...

    Text Solution

    |

  19. A stone is thrown vertically upwards. When stone is at a height half o...

    Text Solution

    |

  20. (a) What does |(dv)/(dt)| and (d|v|)/(dt) represent? (b) Can these be ...

    Text Solution

    |