Resultant of vec A and vec B makes an angle α with vec A and β with vec B ,

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3-1.Vectors

easy

The resultant of $\vec A$ and $\vec B$ makes an angle $\alpha $ with $\vec A$ and $\beta $ with $\vec B$,

A

$\alpha < \beta $

B

$\alpha < \beta $ if $A < B$

C

$\alpha < \beta $ if $A > B$

D

$\alpha < \beta $ if $A = B$

Solution

$\overrightarrow{ A }=\overrightarrow{ R } \cos \alpha$

$\overrightarrow{ B }=\overrightarrow{ R } \cos \beta$

If $\alpha < \beta$

Then, $\cos \alpha > \cos \beta$

$\overrightarrow{ R } \cos \alpha>\overrightarrow{ R } \cos \beta$

Hence, hence, $\vec{A} > \vec{B}$

So, we can say that, if $\vec{A} > \vec{B}, \alpha < \beta$

Standard 11

Physics

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