Question

if cross product of vector P and Q is equal to zero vector and cross product of vector Q and R is equal to also zero vector then find the value of cross product of vector P and vector R
options are......
a) 0
b) AC sin theta
c) AC cos theta
d) ab tan theta

Answer 1

here is ur answer miss

We are given that P × Q = 0, and Q × P = 0. From vector algebra we know that magnitude of P× Q is

| P × Q| = |P|×|Q|× Sin ß, where ß is the angle between P and Q.

P × Q = 0 ==> |P ×Q | = 0; ==> |P|× |Q| × Sin ß =0

This implies either;

1) P=0, or,
2) Q= 0, or
3) Both P, Q= 0, or
4) Angle ß= 0° or 180° . That is vectors P andQ are parallel or anti-parallel to each other.

Answer 2

Answer is 0..


By the given condition

P vector × Q vector = Q vector × R vector
=>P vector = Q vector

so,
P vector × Q vector=PQ sin theta ň

if P vector =Q vector
theta is O°
so sin theta =0
so P vector × Q vector = 0