Vector Algebra Question 13
Question: If $\overrightarrow{F_1}=\hat{i}-\hat{j}+\hat{k}, \overrightarrow{F_2}=-\hat{i}+2 \hat{j}-\hat{k}$, $\overrightarrow{F_3}=\hat{j}-\hat{k}, \vec{A}=4 \hat{i}-3 \hat{j}-2 \hat{k}$ and $\vec{B}=6 \hat{i}+\hat{j}-3 \hat{k}$, then the scalar product of $\overrightarrow{F_1}+\overrightarrow{F_2}+\overrightarrow{F_3}$ and $\overrightarrow{A B}$ will be
[Roorkee 1980]
Options:
A) 3
B) 6
C) 9
D) 12
Show Answer
Answer:
Correct Answer: C
Solution:
- $ \Sigma ,\mathbf{F}=2\mathbf{j}-\mathbf{k}, $ $ \overrightarrow{AB}=2\mathbf{i}+4\mathbf{j}-\mathbf{k} $ , \ $ \Sigma ,\mathbf{F},.,\overrightarrow{AB}=8+1=9. $
BETA
