Kinematics Question 151
Question: Unit vector parallel to the resultant of vectors $ \vec{A}=4\hat{i}-3\hat{j} $ and $ \vec{B}=8\hat{i}+8\hat{j} $ will be [BHU 1995]
Options:
A) $ \frac{24\hat{i}+5\hat{j}}{13} $
B) $ \frac{12\hat{i}+5\hat{j}}{13} $
C) $ \frac{6\hat{i}+5\hat{j}}{13} $
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
Resultant of vectors $ \overrightarrow{A} $ and $ \overrightarrow{B} $
$ \overrightarrow{R}=\overrightarrow{A}+\overrightarrow{B}=4\hat{i}-3\hat{j}+8\hat{i}+8\hat{j} $
$ =12\hat{i}+5\hat{j} $
$ \hat{R}=\frac{\overrightarrow{R}}{|R|}=\frac{12\hat{i}+5\hat{j}}{\sqrt{{{(12)}^{2}}+{{(5)}^{2}}}} $
$ =\frac{12\hat{i}+5\hat{j}}{13} $
BETA
