MCQ
Angle between the vectors $(\hat i + \hat j)$ and $(\hat j - \hat k)$ is ........ $^o$
- A$90$
- B$0$
- C$180$
- ✓$60$
✓
Answer
Correct option: D.
$60$
d
(d) $\cos \theta = \frac{{\vec A.\vec B}}{{|\vec A||\vec B|}} = \frac{1}{{\sqrt 2 \sqrt 2 }} = \frac{1}{2}$ $\theta = 60^\circ $
(d) $\cos \theta = \frac{{\vec A.\vec B}}{{|\vec A||\vec B|}} = \frac{1}{{\sqrt 2 \sqrt 2 }} = \frac{1}{2}$ $\theta = 60^\circ $
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