MCQ
If  $ a$  and $b$ are unit vectors such that $a \times b$ is also a unit vector, then the angle between $a$  and $ b$ is
  • A
    $0$
  • B
    $\frac{\pi }{3}$
  • $\frac{\pi }{2}$
  • D
    $\pi $

Answer

Correct option: C.
$\frac{\pi }{2}$
c
(c) $|a \times b|\, = 1 \Rightarrow \,\,|\sin \theta |\, = 1 \Rightarrow \sin \theta = 1 \Rightarrow \theta = \frac{\pi }{2}$.

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