Two plane mirrors of length L are separated b | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The light from man $M_1$ hits the mirrors and then reaches man $M_2$. The positions of the moving man $M_1$ need to be found when the light from h

Vedclass · Accepted Answer

$\frac{4L}{u}$

Vedclass · Answer

(A) The light from man $M_1$ hits the mirrors and then reaches man $M_2$. The positions of the moving man $M_1$ need to be found when the light from him hits the edges of the mirrors to reach the standing man $M_2$ at $O$.Let the line of motion of $M_1$ be at a distance $2L$ from the plane of the mirrors. Let the mirror edges be at $E, F, G, H$ as shown in the figure. The observer $O$ is at a distance $L$ from the gap between the mirrors.Using similar triangles for the upper mirror (edges $E$ and $G$):For edge $E$ (closer to $O$): The distance of $M_1$ from the line passing through $O$ parallel to the mirrors is $x_E$. By similar triangles,$\frac{x_E}{L} = \frac{2L}{L} \implies x_E = 2L$.For edge $G$ (further from $O$): The distance of $M_1$ from the line passing through $O$ is $x_G$. By similar triangles,$\frac{x_G}{L+L} = \frac{2L}{L} \implies x_G = 4L$.The length of the path visible through the upper mirror is $AB = x_G - x_E = 4L - 2L = 2L$.Similarly,for the lower mirror,the visible path length $CD$ is also $2L$.Total visible length $= AB + CD = 2L + 2L = 4L$.Total time $t = \frac{	ext{Total distance}}{u} = \frac{4L}{u}$.

Similar Questions

During a cloudy day,a primary and a secondary rainbow may be created,then the:

Two plane mirrors are at an angle such that a ray incident on one mirror undergoes a total deviation of $240^o$ after two reflections. Which of the following statements is correct?

$A$ prism having an apex angle $4^o$ and refractive index $1.5$ is located in front of a vertical plane mirror as shown in the figure. Through what total angle is the ray deviated after reflection from the mirror (in $^o$)?

The mirrors are perpendicular to each other as shown in the figure. $A$ light ray $AB$ is incident on the mirror $M_1$. The reflected ray then undergoes a reflection from the mirror $M_2$. The final ray after reflection from $M_2$ will be parallel to the incident ray, if

Two light sources with equal luminous intensity are placed at a distance of $1.2\, m$ from each other. Where should a screen be placed between them such that the illuminance on one of its faces is four times that on the other face?

Vedclass Test Series

Exam Paper Generator

Online Exam Module