Rankers Physics

Rotational Kinetic Energy: Practice Problem & Solution

What is moment of inertia in terms of angular momentum (L) and kinetic energy (K)
\[ \frac{L²}{K} \]
\[ \frac{L²}{2K} \]
\[ \frac{L}{2K^{2}} \]
\[ \frac{L}{2K} \]

Solution Explained:

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

\[ K = \frac{1}{2}I \omega^{2} \]

and

L = I ω ⇒  Substituting we get,

\[ I= \frac{L²}{2K} \]

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