Question

The vector projection of a vector $3\hat{i}+4\hat{k}$ on y-axis is:

• A. 5
• B. 4
• C. 3
• D. zero

Answer 1

Answer: (D)

The vector projection of vector $\vec{A}$ on $y$-axis is
$=\vec{A}\cdot \hat{j}$
$\therefore$ Vector projection $=(3\hat{i}+4\hat{k})\cdot \hat{j}$
$=0$