What is the effect when light enters from a rarer medium to a denser medium? Explain with diagram

What happens to the wavelength of light when it goes from rarer to denser medium?

What is ether medium?

What is ether medium?

Can total inrternal reflection take place,when light travesl from rarer to denser medium?

When a beam of light passes form optically rarer medium to optically denser medium,it bends…….the normal.

For a spherical surface,when refraction takes place from a rarer medium (mu_1) to a denser medium (mu_2) , we write -(mu_1)/u + (mu_2)/v = ( mu_2-mu_1)/R where the symbols have their usual meanings. Now suppose that the object is placed in the denser to the rarer medium . Then, rewrite the above equation.