Total Internal Reflection

A small coin is resting on the bottom of a beaker filled with a liquid. A ray of light from the coin travels up, to the surface of the liquid and moves along its surface (see figure). 

How fast is the light traveling in the liquid?

1.		2.
3.		4.

A ray of light travelling in a transparent medium of refractive index falls on a surface separating the medium from the air at an angle of incidence of . For which of the following value of $$, the ray can undergo total internal reflection?
1.
2.
3.
4.

Which of the following is not due to total internal reflection?

1.	Difference between apparent and real depth of the pond
2.	Mirage on hot summer days
3.	Brilliance of the diamond
4.	Working of optical fibre

Pick the wrong statement in the context with a rainbow.

1.	Rainbow is a combined effect of dispersion, refraction, and reflection of sunlight.
2.	When the light rays undergo two internal reflections in a water drop, a secondary rainbow is formed.
3.	The order of colors is reversed in the secondary rainbow.
4.	An observer can see a rainbow when his front is towards the sun.

In total internal reflection when the angle of incidence is equal to the critical angle for the pair of media in contact, what will be the angle of refraction?

1.
2.
3.
4.	equal to the angle of incidence

If the critical angle for total internal reflection from a medium to vacuum is , the velocity of light in the medium is:

1.		2.
3.		4.

Two transparent media and are separated by a plane boundary. The speeds of light in those media are m/s and m/s, respectively. The critical angle for a ray of light for these two media is:

1.		2.
3.		4.

Light travels a distance in time in air and in time in another denser medium. What is the critical angle for this medium?

1.		2.
3.		4.