# Angular Momentum of a Moving Particle

Mark Zhu

## Homework Statement

A point particle travels in a straight line at constant
speed, and the closest distance it comes to the origin of coordinates
is a distance l. With respect to this origin, does the particle
have nonzero angular momentum? As the particle moves along its
straight-line path, does its angular momentum with respect to the
origin change?

L = r x p

## The Attempt at a Solution

Since there are no external torques applied to this particle system, I assume the angular momentum doesn't change. However, since the position vector of the particle changes over time and the linear momentum vector remains constant, wouldn't the angular momentum vector also change looking at the L = r x p
equation?

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## Homework Statement

A point particle travels in a straight line at constant
speed, and the closest distance it comes to the origin of coordinates
is a distance l. With respect to this origin, does the particle
have nonzero angular momentum? As the particle moves along its
straight-line path, does its angular momentum with respect to the
origin change?

L = r x p

## The Attempt at a Solution

Since there are no external torques applied to this particle system, I assume the angular momentum doesn't change. However, since the position vector of the particle changes over time and the linear momentum vector remains constant, wouldn't the angular momentum vector also change looking at the L = r x p
equation?
I see this is marked solved. Please confirm with a post to the thread.

Mark Zhu
Yes, it is solved. Thanks.