Question

A vector can always have_____________

(a) Only one component along any of the axis

(b) Only two components along any of the axis

(c) Only three components along any of the axis

(d) A unit vector along the direction perpendicular to its direction

The question was asked in quiz.

I'm obligated to ask this question of Cartesian Vectors topic in portion Force Vectors of Engineering Mechanics

Answer 1

Right answer is (c) Only three components along any of the axis

The explanation is: All vectors have three components, whether they are zero or not. And unit vector is always in the direction of its vector. And the unit vector has the magnitude equal to unity. This means unit vector is the vector in the direction of the original vector and the magnitude of the same is unity.