Rankers Physics

Moment of Inertia: Practice Problem & Solution

A wire of mass m and length L is bent in the form of a circular ring. The moment of inertia of the ring about its axis is
mL²
mL²/ 4π²
mL²/ 2π²
mL²/ 8π²

Solution Explained:

To solve this problem, we apply the core principles of Moment of Inertia. Understanding the underlying formula is key to arriving at the correct answer below:

Let the radius of Ring formed is R. Then 

2πR= L ⇒ R = L/2π

Moment of Interia= m (L/2π)²= mL²/ 4π²

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