Auniform, thin, solid door has height 2.20 m, width 0.870 m, and mass 23.0 kg. (a) find its moment of inertia for rotation on its hinges. (b) is any piece of data unnecessary

The solution for this problem is:

a.The moment of inertia of the thin door rotating about the hinges axis is given by:

I = 1/3 mw^2 is to solve for the inertia, where: m is the mass and w is the width

= 23.0 x 0.870^2 / 3

= 17.4087 / 3

= 5.8029 kg m^2

b.The height of the door is not required for this calculation.

The answer is a.  i hope this