Write the conditions for total internal reflection to takeplace?

What is total internal reflection of light ? What are the two essential conditions for total internal reflection to take place ?

Total inrternal reflection tkes place

State the condition of total internal reflectoin to take place at an interface separating two transparent media. Hence derive the expression for the critical angle in terms of speed of light in two media.

State the condition of total internal reflection. Calculate the speed of light in the medium whose critical angle of 45^@ .

For the given incident ray as shown in the figrue,the condition of total interna reflection of the ray will be satisfied,if the refracrtive index of block will be .

Define critical angle for total internal reflection.

If the critical angle for total internal reflection from medium to vacuum is 30^@ , then what is the velocity of light in the medium ?