JEE Advanced · Physics · 8. Rotational Motion
Two thin circular discs of mass m and 4m, having radii of a and 2a, respectively, are rigidly fixed by a massless, right rod of length through their center. This assembly is laid on a firm and flat surface, and set rolling without slipping on the surface so that the angular speed about the axis of the rod is . The angular momentum of the entire assembly about the point 'O' is (see the figure). Which of the following statement(s) is(are) true?
- A The magnitude of angular momentum of the assembly about its center of mass is
- B The magnitude of the z - component of
- C The magnitude of angular momentum of center of mass of the assembly about the point O is 81
- D The center of mass of the assembly rotates about the z-axis with an angular speed of
Answer & Solution
Correct Answer
(D) The center of mass of the assembly rotates about the z-axis with an angular speed of
Step-by-step Solution
Detailed explanation
Magnitude of angular momentum of the assembly about its centre of mass =
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