question_answer 41)

                  Figure shows two identical particles 1 and 2, each of mass m, moving in opposite directions with same speed \[\upsilon \] along parallel lines. At a particular instant, \[{{r}_{1}}\] and \[{{r}_{2}}\] are their respective position vectors drawn from point A which is in the plane of the parallel lines.                 Choose the correct options:                 (a) Angular momentum I1 of particle 1 about A is \[{{l}_{1}}=m\upsilon {{r}_{1}}e\]                 (b) Angular momentum l2 of particle 2 about A is \[{{l}_{2}}=m\upsilon {{r}_{2}}e\]                 (c) Total angular momentum of the system about A is \[l=m\upsilon ({{r}_{1}}+{{r}_{2}})e\] (d) Total angular momentum of the system about A is \[l=m\upsilon ({{d}_{2}}-{{d}_{1}})\otimes \]                 e represents a unit vector coming out of the page.                 \[\otimes \] represents a unit vector going into the page.                

Answer:

                  (a, d) L = linear momentum \[\times \,\bot \] distance of the particle from the axis of rotation.