Question

For the rolling of the body right handed coordinate system means (consider the mentioned axis to be positive)?

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

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

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

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

This question was posed to me in an interview.

The above asked question is from Rolling Resistance topic in section Friction of Engineering Mechanics

Answer 1

Right choice is (a) Thumb is z-axis, fingers curled from x-axis to y-axis

The 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 axis will not create many problems. The right handed coordinate system is universal throughout.