Question

What is a zero vector ?

Answer 1

We define a vector as an object with a length and a direction. However, there is one important exception to vectors having a direction: the zero vector, i.e., the unique vector having zero length. With no length, the zero vector is not pointing in any particular direction, so it has an undefined direction.

Answer 2

The meaning of a zero position vector is a position at the origin of your coordinate system. Similarly, the meaning of a zerodisplacement vector is a vector which represents not being displaced from the origin. The meaning of a velocity vector with all coefficients zero is: not going anywhere in any direction.

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