Vectors Question 196

Question: The angle between two vector $ \overrightarrow{A}\And \overrightarrow{B} $ is $ \theta $ . vector $ \overrightarrow{R} $ is the resultant of vectors $ \overrightarrow{A}\And \overrightarrow{B}, $ if $ \overrightarrow{R} $ makes an angle $ \frac{\theta }{2} $ with $ \overrightarrow{A} $ then

Options:

A) A = 2B

B) A = B/2

C) A = B

D) AB = 1

Show Answer

Answer:

Correct Answer: C

Solution:

[c] From given situation vector diagram is drawn as shown in figure. $ \angle ZXY+\angle YZX=\angle ZYU $
$ \Rightarrow $ $ \angle YZX=\frac{\theta }{2} $ So XYZ is an isosceles triangle so $ |\overrightarrow{A}|=|\overrightarrow{B}| $