Question

What is the direction of the orbital (translational) angular momentum of the comet shown in the figure relative to the Sun?

Short answer

Direction of angular momentum is in negative Z- direction.

Step-by-step solution

Definition of Angular Momentum

Angular momentum is a measure of rotational motion.

Translational (or “orbital”) angular momentum describes motion such as the orbit of the Earth around the Sun. Rotational (or "spin") angular momentum describes motion such as the revolution of the Earth around its own axis.

Momentum Principle relates a change in momentum to the net force on a system, the Angular Momentum Principle relates a change in angular momentum to the net torque, or twist, applied to a system.

Direction of Comet relative to Sun

Applying the right-hand rule, the comet's translational angular momentum shown in fig.1 is in the negative z direction: inwards the page.

Fig.1

Therefore, the direction of angular momentum is in negative Z- direction.