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This question has Statement land Statement 2.                                           [JEE ONLINE 12-05-2012]

Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement 1: When moment of inertia/of a body rotating about an axis with angular speed \[\omega \]increases, its angular momentum L is unchanged but the kinetic energy K increases if there is no torque applied on it.

Statement 2: \[L=I\omega ,\] kinetic energy of rotation \[=\frac{1}{2}I{{\omega }^{2}}\]

A)         Statement 1 is true, Statement 2 is true, Statement 2 is not the correct explanation of Statement 1.

B)        Statement 1 is false, Statement 2 is true.

C)   Statement 1 is true, Statement 2 is true. Statement 2 is correct explanation of the Statement 1.

D)        Statement 1 is true, Statement 2 is false.

Correct Answer: B

Solution :

[b] As so L increases with increase in co. Kinetic energy depends on an angular velocity' co' and moment of inertia of the body I.             i.e.,