Vector Algebra Question 169
Question: If $ \mathbf{a}=\mathbf{i}+2\mathbf{j}+3\mathbf{k},,\mathbf{b}=-\mathbf{i}+2\mathbf{j}+\mathbf{k} $ and $ \mathbf{c}=3\mathbf{i}+\mathbf{j}, $ then the unit vector along its resultant is
[Roorkee 1980]
Options:
A) $ 3\mathbf{i}+5\mathbf{j}+4\mathbf{k} $
B) $ \frac{3\mathbf{i}+5\mathbf{j}+4\mathbf{k}}{50} $
C) $ \frac{3\mathbf{i}+5\mathbf{j}+4\mathbf{k}}{5\sqrt{2}} $
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
- $ \mathbf{R}=3\mathbf{i}+5\mathbf{j}+4\mathbf{k}\Rightarrow \mathbf{\hat{R}}=\frac{3\mathbf{i}+5\mathbf{j}+4\mathbf{k}}{5\sqrt{2}}. $
BETA
