Phys 202 1st Edition Lecture 22Outline of Last Lecture I. The movement and radiation of lightOutline of Current Lecture II. Snell’s lawIII. Example problemsCurrent LectureSnell’s law:Sometimes, when light enters a medium other than air, the path of the light is refracted, meaning that the path of the light changes by some degree, depending on the medium it enters. Light refracts throughdifferent mediums because the speed of light is different through different mediums (as opposed to the constant through a vacuum or air). Light will take whichever path from point a to point b that takes the least amount of time. The refraction angle of light can be measured using Snell’s rule, which is nsin(θi)=n2sin(θ2) Where θi is the angle at which the light hits the medium and θ2 is the angle of the refracted light throughthe medium. n defines the medium that light travels through (like water) and is equal to the velocity of light in the vacuum over the velocity of light. Because n of a vacuum (or air) is 1, n is always greater than or equal to one. For example, the n of water is equal to 1.33, n of glass is equal to 1.78, and n of diamond is about 4. n is the index of refraction.Example Problems:1. The figure below shows the path of light traveling through several different mediums. What are the refraction angles through each different medium? N1=1.27 θ1=22.4 N2=1.4 θ2 θ3 N3=1.32These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.N41.51 θ4Using Snell’s law to solve for this problem, we find that;N1sin(θ1)=n2sin(θ2)Θ2=sin-1[(1.27/1.4)Sin(22.4)]=20.2⁰Now just repeat for the other mediums using the following equalities;N2sin(θ2)=n3sin(θ3)N3Sin(θ3)=n4sin(θ4)2. A fish tank filled with water is made of flat glass walls of n = 1.78. What is the maximum angle of incidence for a light ray within the water to strike the glass wall and still emerge to the outside air? (n of water is 1.33)To find the maximum angle, we consider the angle of light in air to be
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