Question

What is the approximate moment of inertia of a 210 g, 25-cm-diameter plastic disk spun on an axle through its center by an electric motor?

Answer 1

The approximate moment of inertia of a spinning plastic disk can be calculated using the formula I = (1/4) * m * r^2, where m is the mass of the disk and r is the radius of the disk.

Step-by-step explanation:

The moment of inertia (I) of a disk can be calculated using the formula:

I = (1/4) * m * r^2

Where m is the mass of the disk and r is the radius of the disk.

In this case, the mass of the disk is 210 g (0.21 kg) and the radius is 25 cm (0.25 m). Plugging these values into the formula, we get:

I = (1/4) * 0.21 kg * (0.25 m)^2

Simplifying the equation, we find that the moment of inertia is approximately 0.0103 kg · m².