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The rotational kinetic energy of a body ...

The rotational kinetic energy of a body is E and its moment of inertia is l. The angular momentum is

A

EI

B

`2sqrt(EI)`

C

`sqrt(2EI)`

D

`E//I`

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The correct Answer is:
To find the angular momentum of a body given its rotational kinetic energy \( E \) and its moment of inertia \( I \), we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Formula for Rotational Kinetic Energy**: The rotational kinetic energy \( E \) of a rotating body is given by the formula: \[ E = \frac{1}{2} I \omega^2 \] where \( I \) is the moment of inertia and \( \omega \) is the angular velocity. 2. **Rearrange the Formula to Find Angular Velocity**: From the formula for rotational kinetic energy, we can express \( \omega^2 \) as: \[ \omega^2 = \frac{2E}{I} \] Taking the square root to find \( \omega \): \[ \omega = \sqrt{\frac{2E}{I}} \] 3. **Use the Formula for Angular Momentum**: The angular momentum \( L \) of a body is given by the formula: \[ L = I \omega \] 4. **Substitute \( \omega \) into the Angular Momentum Formula**: Now, substitute the expression for \( \omega \) into the angular momentum formula: \[ L = I \left(\sqrt{\frac{2E}{I}}\right) \] 5. **Simplify the Expression**: This can be simplified as follows: \[ L = I \cdot \sqrt{\frac{2E}{I}} = \sqrt{I^2 \cdot \frac{2E}{I}} = \sqrt{2EI} \] 6. **Final Result**: Therefore, the angular momentum \( L \) in terms of the rotational kinetic energy \( E \) and the moment of inertia \( I \) is: \[ L = \sqrt{2EI} \] ### Conclusion: The angular momentum of the body is given by: \[ L = \sqrt{2EI} \]

To find the angular momentum of a body given its rotational kinetic energy \( E \) and its moment of inertia \( I \), we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Formula for Rotational Kinetic Energy**: The rotational kinetic energy \( E \) of a rotating body is given by the formula: \[ E = \frac{1}{2} I \omega^2 ...
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