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

A rigid body is made of three identical thin rods, each of length .L.

1.	A rigid body is made of three identical thin rods, each of length .L. fastended together in the form of the letter .H.. The body is free to rotate about a horizontal axis that runs along the length of one of the legs of .H.. The body is allowed to fall from rest from a position in which the plane of .H. is horizontal. What is the angular speed of the body when the plane of .H. is vertical ?
Answer» Solution :The moment of inertia of the system about the axis is `I=(4)/(3)mL^(2)`. By conservation of mechanical energy the lose in PE of BODY is equal to the gain in rotational KE. `therefore (3)/(2) MGL =(1)/(2)((4)/(3)mL^(2))OMEGA^(2)` on SOLVING `omega=(3)/(2)sqrt((g)/(L))`