Question

What is the magnitude of resultant of cross product of two parallel vectors a and b?

(a) |a|.|b|

(b) |a|.|b| cos(180)

(c) |a|.|b| sin(180)

(d) 1

The question was posed to me in quiz.

This question is from Computational Geometry topic in chapter Computational Geometry of Data Structures & Algorithms II

Answer 1

The correct choice is (c) |a|.|b| sin(180)

To explain: The resultant of cross product of 2 parallel vectors is always 0 as the angle between them is 0 or 180 degrees. So the answer is |a|.|b| sin(180).