MCQ
Add vectors $\overrightarrow{ A }, \overrightarrow{ B }$ and $\overrightarrow{ C }$ each having magnitude of $50$ unit and inclined to the $X$-axis at angles $45^{\circ}, 135^{\circ}$ and $315^{\circ}$ respectively.
- ✓$50$
- B$55$
- C$70$
- D$85$
✓
Answer
Correct option: A.
$50$
a
Angle between $\vec{B}$ and $\vec{C}=315^{\circ}-135^{\circ}=180^{\circ}$
Angle between $\vec{B}$ and $\vec{C}=315^{\circ}-135^{\circ}=180^{\circ}$
$\therefore$ They balance each other
so sum of these three is $\vec{A}=50$ unit at $45^{\circ}$ from $X$-axis
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