Q. Value of $\lambda$ such that the line $\frac{x - 1}{2} = \frac{y - 1}{3} = \frac{\mathcal{z} - 1}{\lambda}$ is $\bot$ to normal to the plane $\overrightarrow{r} \bullet \left( 2\overrightarrow{i} + 3\overrightarrow{j} + 4\overrightarrow{k} \right) = 0$ is

A) $- \frac{13}{4}$
B) $- \frac{17}{4}$
C) 4
D) None of these
Explanation

(a)
Since line is parallel to the plane vector, $2\overrightarrow{i} + 3\overrightarrow{j} + \lambda\overrightarrow{k}$ is perpendicular to the normal to the plane
$2\overrightarrow{i} + 3\overrightarrow{j} + 4\overrightarrow{k}$
$\Rightarrow 2 \times 2 + 3 \times 3 + 4\lambda = 0$
$\Rightarrow \ \lambda = - \frac{13}{4}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.