Find the unit vector in xy-plane, making an angle 60º with the positive direction of x-axis.
Answer & explanation
Correct answer: option 3
Let is a unit vector in the xy-plane, then \(\vec{r}\) = (cosθ)\(\hat{i}\) +(sinθ)\(\hat{j}\)
Here θ is the angle made by the unit vector with the positive direction of x-axis.
Therefore, for θ= 60º
\(\vec{r}\)= (cos60º)\(\hat{i}\) +(sin60º)\(\hat{j}\)
Hence the required unit vector \(\vec{r}\) = (1/2)\(\hat{i}\) +(√(3)/2)\(\hat{j}\)