Laws of Refraction

Q.

In Snell’s law,

$\frac{\sin i}{\sin r}$ = $\frac{v_1}{v_2}$ = constant
This constant is called as:

1. reflective index

2. light index

3. none of these

4. refractive index

Q.

Find the refractive index of the core of an optical fiber if the critical angle is ${60}^{\circ }$ and the refractive index of the cladding is $\sqrt{3}$?

1. $\sqrt{2}$

2. $2$

3. $3$

4. $2.5$

Q.

Find the refractive index of a medium if the speed of light in that medium is $2.25\times {10}^8\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s$}\right.$?

Q.

For a person sitting near a fire, why do the objects like trees and houses on the other side of the fire appear shifting?

Q. A light ray passes from medium 1 to medium 2 as shown in the diagram. Calculate the refractive index of medium 2 with respect to medium 1.

1. $\sqrt{2}$
2. 2
3. $\frac{1}{\sqrt{2}}$
4. $\frac{1}{2}$

Q. Light rays while entering a denser medium from a rarer medium, bends towards the normal.

1. False
2. True

Q.

Find the value of $\sin {\theta }_{glass}$ in the diagram given below.
Given:
$n_{glass}=1.5$

1. $\frac{\sqrt{3}}{2}$
2. $\sqrt{2}$
3. $\frac{1}{\sqrt{3}}$
4. $\frac{1}{\sqrt{2}}$

Q.

Find the value of $\sin {\theta }_{glass}$ in the diagram given below.
Given:
$n_{glass}=1.5$

1. $\frac{1}{\sqrt{3}}$
2. $\sqrt{2}$
3. $\frac{\sqrt{3}}{2}$
4. $\frac{1}{\sqrt{2}}$

Q.

Find the value of $\sin {\theta }_{glass}$ in the diagram given below.
Given:
$n_{glass}=1.5$

1. $\sqrt{2}$
2. $\frac{1}{\sqrt{3}}$
3. $\frac{1}{\sqrt{2}}$
4. $\frac{\sqrt{3}}{2}$

Q. If the speed of light in a medium is $1.5\times {10}^8$ m/s, then the absolute refractive index of the medium is .

1. $2$
2. $3$
3. $1$