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If L is the angular momentum and I is th...

If L is the angular momentum and I is the moment of inertia of a rotating body, then `(L^(2))/(2I)` represents its

A

Rotational K.E.

B

Total energy (c)

C

Rotational P.E.

D

Translational K.E.

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The correct Answer is:
To solve the problem, we need to analyze the relationship between angular momentum (L), moment of inertia (I), and rotational kinetic energy. ### Step-by-Step Solution: 1. **Understanding Angular Momentum**: The angular momentum (L) of a rotating body is given by the formula: \[ L = I \cdot \omega \] where \(I\) is the moment of inertia and \(\omega\) is the angular velocity. 2. **Expressing Angular Momentum in Terms of \(\omega\)**: From the equation above, we can express \(L\) in terms of \(\omega\): \[ L = I \cdot \omega \] 3. **Calculating \(L^2\)**: To find \(L^2\), we square the expression for \(L\): \[ L^2 = (I \cdot \omega)^2 = I^2 \cdot \omega^2 \] 4. **Finding \(\frac{L^2}{2I}\)**: Now, we substitute \(L^2\) into the expression \(\frac{L^2}{2I}\): \[ \frac{L^2}{2I} = \frac{I^2 \cdot \omega^2}{2I} \] 5. **Simplifying the Expression**: We can simplify the expression: \[ \frac{L^2}{2I} = \frac{I \cdot \omega^2}{2} \] 6. **Identifying the Result**: The expression \(\frac{I \cdot \omega^2}{2}\) is recognized as the formula for rotational kinetic energy (\(K.E_{rot}\)): \[ K.E_{rot} = \frac{1}{2} I \omega^2 \] Thus, we conclude that: \[ \frac{L^2}{2I} = \text{Rotational Kinetic Energy} \] ### Final Answer: \(\frac{L^2}{2I}\) represents the rotational kinetic energy. ---

To solve the problem, we need to analyze the relationship between angular momentum (L), moment of inertia (I), and rotational kinetic energy. ### Step-by-Step Solution: 1. **Understanding Angular Momentum**: The angular momentum (L) of a rotating body is given by the formula: \[ L = I \cdot \omega ...
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Knowledge Check

  • If L is the angular momentum and I is the moment of inertia of a rotating body, then (L_(2))/(21) represents

    A
    rotational potential energy
    B
    total energy
    C
    rotational kinetic energy
    D
    translational kinetic energy
  • Thye angular momentum and the moment of inertia are respectively

    A
    vector and tensor quantities
    B
    scalar and vector quantities
    C
    vector and vector quantities
    D
    scalar and scalar quantities
  • According to the principle of conservation of angular momentum, if moment of inertia of a rotating body decreases, then its angular velocity

    A
    decreases
    B
    increases
    C
    remains constant
    D
    becomes zero
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