Kinematics Question 589
Question: The condition for $ \overrightarrow{A}+\overrightarrow{B} $ to be perpendicular to $ \overrightarrow{A}-\overrightarrow{B} $ it’s that
Options:
A) $ |\overrightarrow{A}|=|\overrightarrow{B}| $
B)$ \overrightarrow{\text{A}}\text{=}\overrightarrow{\text{B}} $
C) $ \overrightarrow{\text{B}}\text{ =}\text{0 }~ $
D)$ |\overrightarrow{\text{A}}\text{+}\overrightarrow{\text{B}}|\text{= }|\overrightarrow{\text{A}}-\overrightarrow{\text{B}}| $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ (\vec{A}+\vec{B}) .\vec{A}- \vec{B}=0 $
or $ \vec{A}{.}\vec{A}+\vec{B} {.}\vec{A}-\vec{A} {.}\vec{B}-\vec{B} {.}\vec{B}=0 $
$ \therefore \text{A=B}\text{.} $
