A large glass slab $(μ = 5 / 3)$ of thickness $8 c m$ is placed over a point source of light on a plane surface. It is seen that light emerges out of the top surface of the slab from a circular area of radius $R c m$ . What is the value of $R$ ?

Open in App

Solution

In the given question. $μ = \frac{5}{3}, h = 8 c m$
The situation is similar as given in the concept and as shown in the figure
$r = \frac{h}{tan c} = \frac{h}{\sqrt{μ^{2} - 1}} = \frac{8}{\sqrt{(\frac{5}{3})^{2} - 1}} = \frac{8 \times 3}{4} = 6 c m$
(Here, $c$ is the critical angle of incidence)

Suggest Corrections

Similar questions

Q. A large glass slab

(μ = 5 / 3)

of thickness

8

cm is placed over a point source of light on a plane surface. It is seen that light emerges out of the top surface of the slab from a circular area of radius R cm. What is the value of R?

Q. A ray of light is incident normally on a glass slab of thickness

5

cm and refractive index

1.6

. The time taken to travel by a ray from source to surface of slab is same as to travel through glass slab. The distance of source from the surface is :

Q. In the diagram shown below, a point source O is placed vertically below the center of a circular plane mirror. The light rays starting from the source are reflected from the mirror such that a circular area A on the ground receives light. Now, a glass slab is placed between the mirror and the source O. What will the magnitude of the new area on the ground receiving light? Assume the width of the slab to be very large.

A point object O is placed in front of a transparent slab at a distance x from its closer surface. It is seen from the other side of the slab by light incident nearly normally to the slab. The thickness of the slab is t and its refractive index is $μ .$ The apparent shift in the position of the object is

Q. A ray of light strikes a glass slab

(R . l = μ)

of finite thickness

t

. The emerging light is

Join BYJU'S Learning Program

A large glass slab (μ=5/3) of thickness 8 cm is placed over a point source of light on a plane surface. It is seen that light emerges out of the top surface of the slab from a circular area of radius R cm. What is the value of R?

In the given question. μ=53,h=8cmThe situation is similar as given in the concept and as shown in the figurer=htanc=h√μ2−1=8√(53)2−1=8×34=6cm(Here, c is the critical angle of incidence)

A large glass slab $(μ = 5 / 3)$ of thickness $8 c m$ is placed over a point source of light on a plane surface. It is seen that light emerges out of the top surface of the slab from a circular area of radius $R c m$ . What is the value of $R$ ?

In the given question. $μ = \frac{5}{3}, h = 8 c m$
The situation is similar as given in the concept and as shown in the figure
$r = \frac{h}{tan c} = \frac{h}{\sqrt{μ^{2} - 1}} = \frac{8}{\sqrt{(\frac{5}{3})^{2} - 1}} = \frac{8 \times 3}{4} = 6 c m$
(Here, $c$ is the critical angle of incidence)