Absolute and Relative Refractive Index

Q.

One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face, forms an image 12 cm behind the silvered face. The refractive index of the glass is :

1. 0.4

2. 0.8

3. 1.2

4. 1.6

Q.

The refractive index of four mediums A, B, C, and D are $1.31$, $1.65$, $1.44$, $1.50$ respectively the velocity of light is maximum in which? And how

Q.

The refractive index of diamond is 2.42 and that of carbon disulphide is 1.63. Calculate the refractive index of diamond with respect to carbon disulphide.

1. 2.42

2. 0.67

3. 1.48

4. 1.63

Q. A student carries out the experiment of tracing the path of ray of light through a rectangular glassslab, for two different values of angle of incidence \angle i = 30 and \angle=45. Find the set of value of angleof refraction (Lr) and the angle of emergence (Le), She is likely to observe in two cases.

Q. The velocity of light in glass whose refractive index with respect to air is $1.5$, is $2\times {10}^8{\text{m s}}^{-1}$, and in a certain liquid, the velocity of light is found to be $2.5\times {10}^8{\text{m s}}^{-1}$. Find the refractive index of the liquid with respect to air.

Q.

Fill in the blanks :

(a) Water is optically ___ than air.

(b) Air is optically ___ than glass.

(c) When a ray of light travels from water to air, it bends ___ the normal.

(d) When a ray of light travels from air to glass, it bends ___ the normal.

(e) When white light passes through a prism, it ___

(f) The splitting of white light into its constituent colours is called ___

(g) A ___ mirror is obtained on silvering the outer surface of a part of a hollow glass sphere.

(h) Radius of curvature of a spherical mirror is ___ its focal length.

(i) The angle of incidence for a ray of light passing through the centre of curvature of aspherical mirror is ___

(j) A ___ mirror always forms a virtual image.

(k) A concave mirror forms a virtual image for an object placed ___

Ans. (a) denser (b) rarer (c) away from (d) towards (e) disperses (f) dispersion

(g) concave (h) two times (i) $0^{\circ }$ (j) convex (k) between pole and focus

Q.

The velocity of light in glass whose refractive index with respect to air is $1.5$ is $2\times {10}^{8}m{s}^{-1}$and in certain liquid, the velocity of light is found to be $2.50\times {10}^{8}m{s}^{-1}$. Find the refractive index of that liquid with respect to air.

1. 1.5

2. 1.6

3. 1

4. 1.2

Q. Define refractive index. Mention its SI unit.

Q. Which of the following are the possible refractive indices of optical media?

1. $2.42$
2. $1.54$
3. $0.85$
4. $1.77$

Q.

Relative refractive index can be:

1. equal to 1

2. greater than 1

3. smaller than 1

4. None of these

Q. The relative refractive index of a pair of media could be:

1. $=1$
2. $<1$
3. $>1$
4. $=0$

Q. Which of the following option correctly relates refractive index and speed of light in a transparent medium?

Q. The ratio of SI unit to the CGS unit of planck's constant is :

1. $1:1$
2. ${10}^6:1$
3. ${10}^7:1$
4. ${10}^4:1$

Q. A bird in air looks at a fish directly below it, inside a transparent liquid in a container. If distance of bird as estimated by the fish is $h_2$ and the distance of fish as estimated by bird is $h_1$, then refractive index of the liquid is

1. $\frac{h_1}{h_2}$
2. $\frac{h_2+h_1}{h_1-h_2}$
3. $\frac{h_1-h_2}{h_1+h_2}$
4. $\frac{h_2}{h_1}$