MCQ
Two vectors $\vec A$ and $\vec B$ have magnitudes $2$ and $1$ respectively. If the angle between $\vec A$ and $\vec B$ is $60^o$, then which of the following vectors may be equal to $\frac{{\vec A}}{2} - \vec B$
- A
- ✓
- C
- D
✓
Answer
Correct option: B.
b
$\overrightarrow{\mathrm{A}}=\cos 60^{\circ} \hat{\mathrm{i}}+\sin 60^{\circ} \hat{\mathrm{j}} \quad$ and $\overrightarrow{\mathrm{B}}=\hat{\mathrm{i}}$
$\overrightarrow{\mathrm{A}}=\cos 60^{\circ} \hat{\mathrm{i}}+\sin 60^{\circ} \hat{\mathrm{j}} \quad$ and $\overrightarrow{\mathrm{B}}=\hat{\mathrm{i}}$
$\overrightarrow{\mathrm{A}}-\overrightarrow{\mathrm{B}}=-\frac{1}{2} \hat{\mathrm{i}}+\frac{\sqrt{3}}{2} \hat{\mathrm{j}} \Rightarrow$ $II$ quadrant
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