Question

Vector $\overrightarrow{A}$ is 2 cm long and is ${60}^{\circ }$ above the +ve X axis. Vector $\overrightarrow{A}$ is 2 cm long and is ${60}^{\circ }$ below the x - axis in the fourth quadrant. The value of $\overrightarrow{A}$ + $\overrightarrow{B}$ is

• A. 2 cm along -x axis
• B. 2 cm along +x axis
• C. 4 cm along -x axis
• D. 4 cm along +x axis

Answer 1

The correct option is B

2 cm along +x axis

$\overrightarrow{R}$ = $\overrightarrow{A}$ + $\overrightarrow{B}$

$\overrightarrow{R}$ = 2 cos ${60}^{\circ }$ $\hat{i}$ + 2 sin ${60}^{\circ }$ $\hat{j}$ + 2 cos ${60}^{\circ }$ $\hat{i}$ - 2 sin ${60}^{\circ }$ $\hat{j}$

$\overrightarrow{R}$ = 4 cos ${60}^{\circ }$ $\hat{i}$