Question

Angular momentum is:
A) A scalar
B) A polar vector
C) An axial vector
D) Not a physical quantity

Answer 1

Hint: Recall that the momentum is defined as the product of mass and the velocity of the object. If any object has some mass and is in motion, then it possesses momentum. But if an object is rotating, then the momentum related to the object will be known as angular momentum.

Complete answer:
Angular momentum of an object is defined as the product of the moment of inertia and the angular velocity of the object that is rotating. Angular momentum of a body has both magnitude and direction. So it is a vector quantity. It is denoted by the symbol ‘L’.
A vector that does not change its sign if the coordinate system is changed into a new system by the reflection in the origin is known as an axial vector. Also the axial vector is the product of two polar vectors.

Option C is the right answer.

Note: It is important to remember that the axial vectors act along the axis of rotation of the body. Also these vectors represent rotational effects. The direction in which the body moves does not indicate the direction of rotation. Also angular momentum is different from linear momentum. If the object is moving in a straight line then it will possess linear momentum. The direction of the angular momentum can be known by using Right Hand Rule as per which if the body is held in the right hand, then the thumb will point in the direction of angular momentum of the body.