VectorA makes equal angles with x, y and z

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Vector$\overrightarrow A $ makes equal angles with $x, y$ and $z$ axis. Value of its components (in terms of magnitude of $\overrightarrow A $) will be

A

$\frac{A}{{\sqrt 3 }}$

B

$\frac{A}{{\sqrt 2 }}$

C

$\sqrt 3 \,A$

D

$\frac{{\sqrt 3 }}{A}$

Vector$\overrightarrow A $ makes equal angles with $x, y$ and $z$ axis. Value of its components (in terms of magnitude of $\overrightarrow A $) will be

Let the components of $\overrightarrow A $ makes angles $\alpha ,\,\beta $and $\gamma $ with $x, y$ and $z$ axis respectively then

$\alpha = \beta = \gamma $

${\cos ^2}\alpha + {\cos ^2}\beta + {\cos ^2}\gamma = 1$

$ \Rightarrow $$3{\cos ^2}\alpha = 1$ $ ⇒ \cos \alpha = \frac{1}{{\sqrt 3 }}$

$\therefore \,\,\,{A_x} = {A_y} = {A_z} = A\cos \alpha = \frac{A}{{\sqrt 3 }}$