Question

A beam of light strikes a sheet of glass at an angle of 57.0° with the normal in air. You observe that red light makes an angle of 38.1° with the normal in the glass, while violet light makes a 36.7° angle. (a) What are the indexes of refraction of this glass for these colors of light? (b) What are the speeds of red and violet light in the glass?

Short answer

(a)The indexes of the glass are 1.36 for red and 1.403 for violet.

(b) The speed of red light in glass isand the speed of violet light in glass is

Step-by-step solution

Snell’s law

The part of the light that continues into the second medium is transmitted rather than reflected, but the transmitted Ray changes direction as it crosses the boundary. Refraction is the transmission of light from one medium to another with a change in direction. Snell's law describes the angles of incidence and refractive right.

Here;

Index of refraction

Index of refraction;

Here;

n is the index of refraction for an optical material

c is the speed of light

v is the speed of light in the material

Because light travels more slowly in the material than in a vacuum, the value of n in any medium other than vacuum is always greater than unity.

Indexes of refraction of the glass

(a) For red light;

For violet light;

Hence, the indexes of the glass are 1.36 for red and 1.403 for violet.

Speed of red and violet light in the glass

(b) For speed of red;

Taking

For speed of violet;

Taking

Hence, the speed of red light in glass isand the speed of violet light in glass is