Question

The expression $\left(\frac{1}{\sqrt{2}}\hat{i}+\frac{1}{\sqrt{2}}\hat{j}\right)$ is a

• A. Unit vector
• B. Null vector
• C. Vector of magnitude $\sqrt{2}$
• D. Scalar

Answer 1

Answer: (A)

$\vec{P}=\frac{1}{\sqrt{2}}\hat{i}+\frac{1}{\sqrt{2}}\hat{j}$
$\therefore |\vec{P}|=\sqrt{{\left(\frac{1}{\sqrt{2}}\right)}^2+{\left(\frac{1}{\sqrt{2}}\right)}^2}=1$
$\therefore$ It is a unit vector.