Calculate the moment of inertia of uniform circular disc of mass 500g, radius 10cm about 1.the diameter of the disc. 2. the axis tangent to the disc parallel to its diameter 3.the axis through the center of the disc and perpendicular to its plane

Mass of the disc is equal to 500 g (m=500 g)

Radius of the disc if equal to 10 cm (r=10 cm)

1.    The diameter of the disc:

D = 1/4 (m) (r)^2

= 1/4 (500) x 10^2 g cm^2

= 12500 g cm^2

2.    The axis tangent to the disc and parallel to its diameter:

= 1/4 (m) (r )^2 + m (r )^2

= 5/4 x 500 x 10^2 g cm^2

= 62500 g cm^2

3.    The axis through the center or the disc and perpendicular to its plane:

= 1/2 (m) (r )^2 – ½ x 500 x 10^2 g cm^2

= 25000 g cm^2

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )