Refraction at Curved Surfaces

Q. The speed of the light in a diamond is 1, 24, 000 km/s. Find the refractive index of diamond if the speed of light in air 3.00, 000 km/s is:

1. 2.25
2. 2.6
3. 2.8
4. 2.4

Q.

The swimming pool appears to be less deep than it actually is. Which phenomenon is responsible for it?

1. Reflection of light

2. Diffusion of light

3. Refraction of light

4. Scattering of light

Q. Parallel light enters from medium 1 to medium 2 for both the cases A and B as shown in figure below. Which of the statement(s) is/are true for the refracted rays in medium 2?
(Refractive index of medium 2 is higher than the refractive index of medium 1)

1. For case A refracted light rays are parallel.
2. For case B refracted light rays are parallel.
3. For case A refracted light rays are diverging.
4. For case B refracted light rays are converging.

Q. What is the unit of refractive index?

1. Hz
2. m/s
3. m
4. It has no unit.

Q.

When a light ray travels from medium 1 to 2, in which of the following cases it bends towards the normal?

1. Air to glass

2. Glass to water

3. Water to air

4. Glass to air

Q.

Find the angle of refraction in the following figure.

1. $si{n}^{-1}\left(\frac{3}{4}\right)$

2. $si{n}^{-1}\left(\frac{3}{8}\right)$

3. $si{n}^{-1}\left(\frac{1}{2}\right)$

4. $si{n}^{-1}\left(\frac{4}{3}\right)$

Q. For a light ray passing from air to water, according to Snell's law:
($n$ represents refractive index of the medium, ${\theta }_{air}$ is the angle of incidence and ${\theta }_{water}$ is the angle of refraction)

1. $n_{air}$ $Sin{\theta }_{air}$ = $n_{water}$ $Sin{\theta }_{water}$
2. $n_{air}$ $Sin{\theta }_{water}$ = $n_{water}$ $Sin{\theta }_{air}$
3. $n_{air}$ $Sin{\theta }_{air}$ $n_{water}$ $Sin{\theta }_{water}$ = 1
4. $n_{air}$ $n_{water}$ = $Sin{\theta }_{water}$ $Sin{\theta }_{air}$

Q. For curved surfaces with very small apertures, incident rays are approximately parallel to the principal axis.

1. False
2. True

Q.

Locate the image of the point object O in the situation shown in the figure. The point C denotes the centre of curvature of the refracting surface.

1. $20cm$, Left
   

2. $30cm$, Left

3. $30cm$, Right

4. $20cm$, Right

Q. A pencil partly immersed in water in a glass tumbler appears to be bent or broken because:

1. Glass tumbler creates an optical illusion.
2. Light ray does not travel in the same direction in all media.
3. Pencil and water react and the light direction changes.
4. Dispersion occurs in water.