If overrightarrow P .overrightarrow Q = PQ, then angle between overrightarrow P and overrightarrow Q

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3-1.Vectors

easy

If $\overrightarrow P .\overrightarrow Q = PQ,$ then angle between $\overrightarrow P $and $\overrightarrow Q $ is ....... $^o$

A

$0$

B

$30$

C

$45$

D

$60$

(AIIMS-1999)

Solution

(a) $\cos \theta = \frac{{\vec P.\vec Q}}{{PQ}} = 1$

$\theta = 0^\circ $

Standard 11

Physics

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