What Happens When A Ray Of Light Enters A Glass Slab From Air?

When a ray of light enters the glass slab from air, its frequency and does not change at all. However, its speed will decrease, and it will bend also. This is called as refraction phenomenon. Its wavelength will also change , and it can be calculated by the following formula,

refractive index x lambda = lambda0

where,

Lambda0 is the wavelength in a vacuum

lambda is the wavelength in the medium