Kinematics Question 443
If $ \vec{a}\times \vec{b}+\vec{c}=0, $ then $ \vec{a}\times \vec{b} $ is
Options:
A) $ \vec{a}\times \vec{b} $
B) $ \vec{c}\times \vec{b} $
C) $ \vec{a}\times \vec{c} $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ \vec{a}+\vec{b}+\vec{c}=0 $
$ \therefore $ $ \vec{a}+\vec{c}=-\vec{b} $
$ \therefore $ $ (\vec{a}+\vec{c})\times \vec{b}=\vec{b}\times \vec{b}=0 $ or $ (\vec{a}\times \vec{b})+(\vec{c}\times \vec{b})=\vec{0} $ or $ \vec{a}\times \vec{b}=\vec{c}\times \vec{b} $
BETA
