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