# 1Q10.30 - Moments of Inertia - Hoops and Disks

Code Number:
1Q10.30
Demo Title:
Moments of Inertia - Hoops and Disks
Condition:
Good
Principle:
Exchange of Potential and Kinetic Energy, Moments of Inertia
Area of Study:
Mechanics
Equipment:
Wood & Metal Disks (Asst.) (Equal Mass), Inclined Plane, and Stop Block.
Procedure:

Video Credit: Jonathan M. Sullivan-Wood.

The only assembly required is to raise one end of the incline up with blocks until the desired angle is achieved.  Some type of stop is then attached to the end of the table so that the disks do not roll off the table after rolling down the incline.

Objects with different numerical coefficients for the moments of inertia may also be rolled down an incline.  The set we have has a hoop, a cylinder, a uniform density ball, a cone, and an object with the mass concentrated in the center.  All of these objects have the same rolling diameter.  The order of these objects will be from slowest to fastest: hoop, cylinder, ball, cone, and center concentrated.  Note that the cone and center concentrated have low mass hoops attached so that they also have the same rolling diameter as the other objects.

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