MCQ
If $\overrightarrow P .\overrightarrow Q = PQ,$ then angle between $\overrightarrow P $and $\overrightarrow Q $ is ....... $^o$
  • $0$
  • B
    $30$
  • C
    $45$
  • D
    $60$

Answer

Correct option: A.
$0$
a
(a) $\cos \theta = \frac{{\vec P.\vec Q}}{{PQ}} = 1$ 

$\theta = 0^\circ $

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