Chapter 29, Problem 48A

When light strikes glass perpendicularly, about 4% of the light is reflected at each surface. Show that the amount of light transmitted through a pane of window glass is approximately 92%.

To determine

To show: the amount of light that is transmitted through a pane of window glass is approximately $92\%$ when the light that strikes glass perpendicularly about $4\%$ of the light. 

Explanation of Solution

Introduction: 

Some of the light will reflect and some of the light will pass through the medium when the light strikes the medium. When the light is incident at an angle, the light passing through the medium gets refracted.

Explanation: 

Double reflection is an optical property in which a single ray of light entering into a particular medium will split into two rays and each travel in a different direction. 

The double reflection can be observed in the materials like glass and calcite when light strikes perpendicular to them. The glass has two reflecting surfaces, and from each surface, $4\%$ of light reflected so, a total of $8\%$ light reflected.

The total light that strikes on the glass is $100\%$ therefore, remain light $92\%$ is transmitted through the glass $\left(100\%-8\%=92\%\right).$

Conclusion: 

The light reflects the light from two surfaces and each of them is $4\%$ so, the remaining $92\%$ light is transmitted through the glass.