Home
Class 11
PHYSICS
A rigid body is made of three identical ...

A rigid body is made of three identical thin rods, each with length fastened together in the form. of letter `H`. The body is free to rotate about a horizontal axis that runs along the length of one of the arms of `H`. The body is allowed to fall from rest from a position in which the plane of the `H` is horizontal. What is the angular speed of the body when the plane of `H` is vertical?

Text Solution

Verified by Experts

Using principle of conservation of mechanical enegy, we have
`(mgl)/2+mgl=1/2Iomega^(2)`
where `omega` is the angular speed of the rod when it becomes vertical and `I=(ml^2/3)+ml^(2)`, assuming mass of eac rod is `m`.
Substituting value of `I` in the above equation, we get
`omega=sqrt((9g)/(4l))`
Promotional Banner

Topper's Solved these Questions

  • RIGID BODY DYNAMICS 2

    CENGAGE PHYSICS ENGLISH|Exercise Exercise 3.2|13 Videos

  • RIGID BODY DYNAMICS 2

    CENGAGE PHYSICS ENGLISH|Exercise Exercise 3.3|21 Videos

  • RIGID BODY DYNAMICS 2

    CENGAGE PHYSICS ENGLISH|Exercise Solved Examples|12 Videos

  • RIGID BODY DYNAMICS 1

    CENGAGE PHYSICS ENGLISH|Exercise Integer|11 Videos

  • SOUND WAVES AND DOPPLER EFFECT

    CENGAGE PHYSICS ENGLISH|Exercise Integer|16 Videos

Similar Questions

Explore conceptually related problems

A uniform rod is rotating about a horizontal axis as shown. The rod is hinged at one of the ends. The rod is released from a vertical position by slightly pushing it. As the rod moves from A to B

A uniform rod of length l is from rest such that it rotates about a smooth pivot. The angular speed of the rod when it becomes vertical is. .

A thin bar of mass M and length L is free to rotate about a fixed horizontal axis through a point at its end. The bar is brought to a horizontal position and then released. The axis is perpendicular to the rod. The angular velocity when it reaches the lowest point is

A uniform rod of length L is free to rotate about an axis passing through O . Inititally the rod is horizontal. The rod is relased from this position. Match column I with column II

The thin rod shown below has mases M and length L. A force F acts at one end as shown and the rod is free to rotate about the other end in horizontal plane. Initial angular acceleration of the rod is :

A half metre scale is pivoted about a horizontal fiictionless pin through one end as shown in Fig. The scale is released from rest in a vertical position. At the instant when the scale is horizontal what is (i) its angular speed and (ii) the magnitude of the angular acceleration.(Given length of rod =1/2 m)

A short magnet is allowed to fall from rest along the axis of a horizontal conducting ring. The distance fallen by the magnet in one second may be

A uniform rod AB of length l and mass m is free to rotate about an Axis passing through A and perpendicular to length of the rod. The rod is released from rest as shown in figure. Given that the moment of inertia of the rod about A is (ml^(2))/3 The initial angular acceleration of the rod will be

Three identical rods, each of length L , are joined to form a rigid equilateral triangle. Its radius of gyration about an axis passing thorugh a corner and perpendicular to plane of triangle is

A uniform rod of length L is free to rotate in a vertical plane about a fixed horizontal axis through B . The rod begins rotating from rest. The angular velocity omega at angle theta is given as