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