Q. A particle is moving in the $x$-$y$ plane with a constant velocity along a line parallel to $x$-axis away from the origin. The magnitude of its angular momentum about the origin
A) Is zero
B) Remains constant
C) Goes on increasing
D) Goes on decreasing
Explanation
(b) Angular momentum$\ = \ $(Linear momentum) $\times$ (perpendicular distance to line of motion
from the axis)
or angular momentum is moment of momentum. Here, the angle goes on decreasing from $90{^\circ}$ but the perpendicular distance to the line of motion remains constant. Therefore, angular momentum is also constant (linear momentum $p = mv$ is constant).
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.