Reflection Refraction of Light
Reflection & Refraction of Light
Law of Reflection:
angle of incidence = angle of reflection
-angles measured from normal
(perpendicular to surface)
-incident ray, reflected ray & normal all lie
regular reflection on same plane
Definition: Regular Reflection - if light falls
on very smooth surface, reflected rays are
parallel to each other (as were the incident
rays)
Definition: Diffuse Reflection - rays are
diffuse reflection reflected in many different directions
Refraction of Light:
Definition: Optically Dense - when speed of light in one medium is slower than that in another
Definition: Refraction - change in direction or bending of light at boundary between 2 media oo-when angle of incidence = 0 , angle of refraction = 0
-speed changes but passes straight through, along the normal -when light travels into a medium where it travels faster, angle of refraction > angle of
incidence OR if light enters less optically dense medium, refracted rays bend away from the normal
-if light enters more optically dense medium, refracted rays bend toward the normal
Definition: Index of Refraction (n) - ratio of the speed of light in a vacuum to its speed into a material
Snell's Law:
"Light moving from smaller n to larger n is bent toward
normal & vice-versa"
nsin,,nsin, iirr
-n is index of refraction for incident medium i
-n is index of refraction for second medium r
, & ,- are angles of incidence & refraction ir
-refractive index (n) can be found by measuring angles of
incidence & refraction
-Snell's Law can be used to find the speed of light in a material (originating from a
vacuum)
c n,svs
n is the index of refraction of the material s8c is the speed of light in a vacuum (3.00 x 10 m/s)
v is the speed of light in the material s
Definition: Total Internal Reflection - occurs when light passes from a more optically
dense medium to a less optically dense one at an angle so great that there is no
refracted ray
Definition: Critical Angle ()- occurs when the refracted ray lies along the boundary of ,c
the medium surface
nr sin,,cni
-any ray that reaches the boundary of medium at an angle greater than cannot leave ,cmedium
-all of the light is reflected ---> total internal reflection
Refraction Refraction at the Critical Angle Total Internal Reflection
,, , r c,, , r c Ai r Ai r Ai r
,,, , i r c G l as s G l as s ,,G l as s ili g h t r a y li g h t r a y
li g h t r a y
-practical applications: fibre optics, internal body probes
Summary of Formulae:
nsin,,nsin,iirr
cn, svs
nrsin,, cni
本文档为【Reflection Refraction of Light】，请使用软件OFFICE或WPS软件打开。作品中的文字与图均可以修改和编辑，
图片更改请在作品中右键图片并更换，文字修改请直接点击文字进行修改，也可以新增和删除文档中的内容。
该文档来自用户分享，如有侵权行为请发邮件ishare@vip.sina.com联系网站客服，我们会及时删除。
[版权声明] 本站所有资料为用户分享产生，若发现您的权利被侵害，请联系客服邮件isharekefu@iask.cn，我们尽快处理。
本作品所展示的图片、画像、字体、音乐的版权可能需版权方额外授权，请谨慎使用。
网站提供的党政主题相关内容(国旗、国徽、党徽..)目的在于配合国家政策宣传，仅限个人学习分享使用，禁止用于任何广告和商用目的。
浙公网安备 33021202002483