MCQ
Two vectors $\vec{A}$ and $\vec{B}$ are at right angles to each other, when
- A$\vec{A} \quad \vec{B} \quad 0$
- B$\vec{A} \quad \vec{B} \quad 0$
- C$\vec{A} \cup \vec{B} \quad 0$
- ✓$\vec{A} \cdot \vec{B} 0$
✓
Answer
Correct option: D.
$\vec{A} \cdot \vec{B} 0$
(d) $\vec{A} \cdot \vec{B}=|\vec{A}| \cdot|\vec{B}| \cdot \cos \theta=\vec{A} \cdot \vec{B} \cdot \cos 90^{\circ}=0$
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