MCQ
If a vector $\vec A$ is parallel to another vector $\vec B$ then the resultant of the vector $\vec A \times \vec B$ will be equal to
  • A
    $A$
  • B
    $\vec A$
  • Zero vector
  • D
    Zero

Answer

Correct option: C.
Zero vector
c
(c) $\overrightarrow A \times \overrightarrow B = AB\sin \theta \,\hat n$

for parallel vectors $\theta = 0^\circ $ or $180^\circ $, $\sin \theta = 0$

$\therefore $ $\overrightarrow A \times \overrightarrow B = \hat 0$

 

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