If a and b are unit vectors such that a b is also a unit vector, … - Vidyadip

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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