Question

A vector is represented by $3\hat{i}+\hat{j}+2\hat{k}$, has length in $XY$ plane

• A. 2
• B. $\sqrt{14}$
• C. $\sqrt{10}$
• D. $\sqrt{5}$

Answer 1

The correct option is C $\sqrt{10}$

We know,

The length in $XY$ plane is due to the $X$ and $Y$ component of the line,

Hence, the $XY$ components are $3i+j$

And length $=\sqrt{3^2+1^2}=\sqrt{1}0$

Option $\text{C}$ is the correct answer