A rotating flywheel can be used as a method to store energy.If it is required that such a device be able to store up to a maximum of 2.00 × 10⁶ J when rotating at 400 rad/s,what moment of inertia is required? A)50.0 kg m² B)25.0 kg m² C)12.5 kg m² D)6.30 kg m²

Question

Quizplus · Accepted Answer

The formula for the rotational kinetic energy of a rotating object is:

KE = (1/2)Iω²

where I is the moment of inertia and ω is the angular velocity.

We are given that the maximum energy that can be stored is 2.00 × 10¹⁶ J and the angular velocity is 400 rad/s. So, we can rearrange the formula to solve for I:

I = (2KE)/(ω²)

Substituting the given values, we get:

I = (2 × 2.00 × 10¹⁶ J)/(400 rad/s)²
I = 25.0 kg m²

Therefore, the moment of inertia required is 25.0 kg m². So, the best choice is B).

A Rotating Flywheel Can Be Used as a Method to Store