Q. Given $\overrightarrow{P} \bullet \overrightarrow{Q} = 0$, then $\left| \overrightarrow{P} \times \overrightarrow{Q} \right|$ is
A) $\left| \overrightarrow{P} \right|\left| \overrightarrow{Q} \right|$
B) Zero
C) 1
D) $\sqrt{PQ}$
Explanation
(a) $\overrightarrow{P}.\overrightarrow{Q} = 0\ \Rightarrow \overrightarrow{P}\bot\overrightarrow{Q}$ or $\theta = 90{^\circ}$
$\left| \overrightarrow{P \times}\overrightarrow{Q} \right| = PQ$ sin$90{^\circ} = PQ$ or $\left| \overrightarrow{P} \right|\ \left| \overrightarrow{Q} \right|$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.