Question

Find a vector normal to a plane consisting of points p1(0,1,0), p2(1,0,1) and p3(0,0,1)

(a) –j – k

(b) –i – j

(c) –i – k

(d) –i – j – k

The question was posed to me by my college director while I was bunking the class.

This is a very interesting question from Position and Distance Vectors topic in chapter Vector Analysis and Applications of Electromagnetic Theory

Answer 1

Correct answer is (a) –j – k

The explanation is: Distance vector from p1 and p2 is a = i – j + k. Distance vector from p1 and p3 is b = –j + k. The vector normal to these points is a X b = -j – k.