Why Is the View Through a Glass Window Not Noticeably Dimmer?
Overview
When light hits a glass surface, some of it is reflected while the rest is transmitted through the glass. The view through a glass window (with a refractive index of 1.5) is not noticeably dimmer than an open window.
Explanation
Calculation of Reflected LightThe reason why the view through a glass window is not significantly dimmer is that only 4% of the incident light is reflected, and the remaining 96% is transmitted through the glass.
To calculate the amount of light that is reflected, we can use the Fresnel equations. The reflectance, R, is calculated using the formula:
R = ((n1 - n2)/(n1 + n2))^2
Where n1 = refractive index of air (1) and n2 = refractive index of glass (1.5). Plugging the values into the equation:
R = ((1 - 1.5)/(1 + 1.5))^2 = (-0.5/2.5)^2 = 0.04
Conclusion
Light Transmission Through GlassDue to the low reflectance coefficient of 4%, the majority of the light entering the glass window is transmitted through it, resulting in a view that is not noticeably dimmer compared to an open window.
if light reflects from all surfaces why is the view through a glass window (nglass = 1.5) not noticeably dimmer than the view with the window open? do the calculation to support your answer.
The view through a glass window is not noticeably dimmer than the view with the window open because only 4% of the light incident on the glass surface is reflected, while the remaining 96% of the light is transmitted through the glass.