Target Exam

CUET

Subject

Section B1

Chapter

Vectors

Question:

Find the vector joining the points $P(2, 3, 0)$ and $Q(-1, -2, -4)$ directed from $P$ to $Q$.

Options:

$3\hat{i} + 5\hat{j} + 4\hat{k}$

$-3\hat{i} - 5\hat{j} - 4\hat{k}$

$-\hat{i} + \hat{j} - 4\hat{k}$

$-3\hat{i} + 5\hat{j} - 4\hat{k}$

Correct Answer:

$-3\hat{i} - 5\hat{j} - 4\hat{k}$

Explanation:

The correct answer is Option (2) → $-3\hat{i} - 5\hat{j} - 4\hat{k}$ ##

Since the vector is to be directed from $P$ to $Q$, clearly $P$ is the initial point and $Q$ is the terminal point. So, the required vector joining $P$ and $Q$ is the vector $\vec{PQ}$, given by

$\vec{PQ} = (-1-2)\hat{i} + (-2-3)\hat{j} + (-4-0)\hat{k}$

i.e. $\vec{PQ} = -3\hat{i} - 5\hat{j} - 4\hat{k}$