Question

In right handed coordinate system which axis is considered to be positive?

(a) The thumb is z-axis, fingers curled from x-axis to y-axis

(b) The thumb is x-axis, fingers curled from z-axis to y-axis

(c) The thumb is y-axis, fingers curled from x-axis to z-axis

(d) The thumb is z-axis, fingers curled from y-axis to x-axis

The question was posed to me during an online exam.

My question comes from Cartesian Vectors in division Force Vectors of Engineering Mechanics

Answer 1

Right option is (a) The thumb is z-axis, fingers curled from x-axis to y-axis

Easiest explanation: As right handed coordinate system means that you are curling your fingers from positive x-axis towards y-axis and the thumb which is projected is pointed to the positive z-axis. Thus visualizing the same and knowing the basic members of the axis will not create many problems.