Home
Class 12
PHYSICS
A mass M is supported by a massless stri...

A mass M is supported by a massless string wound round a uniform cylinder ofmass M and radius R. On releasing the mass from rest, it will fall with acceleration?

A

(a)g

B

(b)g/2

C

(c)g/3

D

(d)2g/3

Text Solution

Verified by Experts

The correct Answer is:
D
`Mgh=1/2Mv^2+1/2Iomega^2` `=1/2Mv^2+1/2[1/2MR^2]omega^2``=1/2Mv^2+1/4Mv^2=3/4Mv^2` `v=sqrt(2ah) because Mgh=3/4Mxx2ah``a=2/3g`. Solve by force /torque and Newton.s law also.
Promotional Banner

Topper's Solved these Questions

  • SYSTEM OF A PARTICLES & ROTATIONAL MOTION

    VMC MODULES ENGLISH|Exercise PRACTICE EXERCISE-1|4 Videos

  • SYSTEM OF A PARTICLES & ROTATIONAL MOTION

    VMC MODULES ENGLISH|Exercise PRACTICE EXERCISE-2|5 Videos

  • SYSTEM OF A PARTICLES & ROTATIONAL MOTION

    VMC MODULES ENGLISH|Exercise IN-CHAPTER EXERCISE F|10 Videos

  • SIMPLE HARMONIC MOTION

    VMC MODULES ENGLISH|Exercise 7-previous year question|46 Videos

  • SYSTEM OF PARTICLES AND ROTATIONAL MOTION

    VMC MODULES ENGLISH|Exercise IMPECCABLE|56 Videos

Similar Questions

Explore conceptually related problems

A mass 'm' is supported by a massless string wound around a uniform hollow cylinder of mass m and radius R. If the string does not slip on the cylinder, with what acceleration will the mass fall or release?

A load of mass m is attached to the end of a string wound on a cylinder of mass M and radius R . The string passes round a pulley. a. Find the acceleration of the cylinder M when it rolls. b. If the coefficient of friction is mu . Find the accelerative of the cylinder when it slips and rolls. c. Find the minimum value of coefficient of friction for which the cylinder rolls always

As shown in the figure, a bob of mass m is tied by a massless string whose other end is wound on a fly wheel Ring of radius r and mass m. When released from rest the bob starts falling vertically. When it has covered a distance of h, the speed of the bob will be :

As shown in the figure, a bob of mass m is tied by a massless string whose other end is wound on a fly wheel Ring of radius r and mass m. When released from rest the bob starts falling vertically. When it has covered a distance of h, the speed of the bob will be :

As shown in the figure, two bobs of masses m & 2m are tied by a massless string which is wound on a fly wheel (disc) of radius r and mass m. When released from rest the bob of mass 2m starts falling vertically. When it has covered distance of h, the angular speed of the wheel will be:

As shown in the figure, two bobs of masses m & 2m are tied by a massless string which is wound on a fly wheel (disc) of radius r and mass m. When released from rest the bob of mass 2m starts falling vertically. When it has covered distance of h, the angular speed of the wheel will be:

As shown in fig., a bob of mass m is tied by a massless string whose other end portion is wound on a fly wheel (disc) of radius r and mass 2m. when released from rest the bob starts falling vertically. The time taken by the bob to descend through a height h, from the initial position, is

As shown in fig., a bob of mass m is tied by a massless string whose other end portion is wound on a fly wheel (disc) of radius r and mass 2m. when released from rest the bob starts falling vertically. The time taken by the bob to descend through a height h, from the initial position, is

One end of a massless string is wound around a cylinder of mass 5 kg and radius 16' cm. The cylinder' is mounted symmetrically on a horizontal axle so 5 that It can freely rotate about its axis, to the other end of the string a mass of 500 gm is attached. Calculate the acceleration of the mass when it is released from rest.

A block of mass m is attached at the end of an inextensible string which is wound over a rough pulley of mass M and radius R figure a. Assume the string does not slide over the pulley. Find the acceleration of the block when released.

VMC MODULES ENGLISH-SYSTEM OF A PARTICLES & ROTATIONAL MOTION-SOLVED EXAMPLES
  1. A wheel of mass M and radius a and M.I. IG (about centre of mass) is s...

    Text Solution

    |

  2. A rod standing vertically on a table falls down. What will be the line...

    Text Solution

    |

  3. A constant torque acting on a uniform circular changes its angular mom...

    Text Solution

    |

  4. A disc rolls over a horizontal floor without slipping with a linear sp...

    Text Solution

    |

  5. If the moment of inertia of a disc about an axis tangential and parall...

    Text Solution

    |

  6. Two particles A and B are moving as shown in figure. At this moment of...

    Text Solution

    |

  7. A circular loop and a disc have the same mass and roll without slippin...

    Text Solution

    |

  8. A wheel initially at rest, is rotated with a uniform angular accelerat...

    Text Solution

    |

  9. A constant horizontal force F is applied on the top of a solid sphere ...

    Text Solution

    |

  10. A wheel of radius r rolls without slipping with a speed v on a horizon...

    Text Solution

    |

  11. A uniform rod of mass m and length l rotates in a horizontal plane wit...

    Text Solution

    |

  12. A cubical block of side a is moving with velocity v on a horizontal sm...

    Text Solution

    |

  13. A mass M is supported by a massless string wound round a uniform cylin...

    Text Solution

    |

  14. A stick of length L and mass M lies on a frictionless horizontal surfa...

    Text Solution

    |

  15. A man spinning in free space can change the moment of inertia of his b...

    Text Solution

    |

  16. A stone of mass m, tied to the end of a string, is whirled around in a...

    Text Solution

    |

  17. A uniform bar of mass m and length L is horizontally suspended from th...

    Text Solution

    |

  18. A block of mass m is at rest under the action of F against the wall as...

    Text Solution

    |

  19. Two men support a uniform horizontal beam at its two ends, if one of t...

    Text Solution

    |

  20. A sphere S rolls without slipping with a constant speed on a plank P. ...

    Text Solution

    |