Vector Algebra Question 326
Question: If a has magnitude 5 and points north-east and vector b has magnitude 5 and points north-west, then $ |\mathbf{a}-\mathbf{b}|,= $
[MNR 1984]
Options:
A) 25
B) 5
C) $ 7\sqrt{3} $
D) $ 5\sqrt{2} $
Show Answer
Answer:
Correct Answer: D
Solution:
- Since $ \mathbf{a},\bot ,\mathbf{b}\Rightarrow \mathbf{a},.,\mathbf{b}=0 $ $ |\mathbf{a}-\mathbf{b}{{|}^{2}}={{(\mathbf{a}-\mathbf{b})}^{2}}=a^{2}+b^{2}-2\mathbf{a},.,\mathbf{b}=25+25 $
$ \Rightarrow |\mathbf{a}-\mathbf{b}|=5\sqrt{2}. $
BETA
