In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or refracted, when entering a material. This is described by Snell's law of refraction, n1 sin θ1 = n2 sin θ2, where θ1 and θ2 are the angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices n1 and n2. The refractive indices also determine the amount of light that is reflected when reaching the interface, as well as the critical angle for total internal reflection, their intensity (Fresnel's equations) and Brewster's angle. The refractive index can be seen as the factor by which the speed and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is v = c/n, and similarly the wavelength in that medium is λ = λ0/n, where λ0 is the wavelength of that light in vacuum. This implies that vacuum has a refractive index of 1, and assumes that the frequency (f = v/λ) of the wave is not affected by the refractive index. The refractive index may vary with wavelength. This causes white light to split into constituent colors when refracted. This is called dispersion. This effect can be observed in prisms and rainbows, and as chromatic aberration in lenses. Light propagation in absorbing materials can be described using a complex-valued refractive index. The imaginary part then handles the attenuation, while the real part accounts for refraction. For most materials the refractive index changes with wavelength by several percent across the visible spectrum. Nevertheless, refractive indices for materials are commonly reported using a single value for n, typically measured at 633 nm. The concept of refractive index applies across the full electromagnetic spectrum, from X-rays to radio waves. It can also be applied to wave phenomena such as sound. In this case, the speed of sound is used instead of that of light, and a reference medium other than vacuum must be chosen. For lenses (such as eye glasses), a lens made from a high refractive index material will be thinner, and hence lighter, than a conventional lens with a lower refractive index. Such lenses are generally more expensive to manufacture than conventional ones. (Wikipedia).
Refraction (1 of 5) What is Refraction? An Explanation
Refraction, A conceptual qualitative explanation. Refraction is the change in direction of a ray of light as it passes from one medium to another. The amount of refraction is determined by the index of refraction of the media and the angle of incidence. For light, refraction follows Snell
From playlist Optics: Ray Diagrams, Reflection, Refraction, Thin Lens Equation
Refraction (5 of 5) Index of Refraction, An Explanation
Describes the index of refraction and show how to calculate the index of refraction. The index of refraction (n) of a material is a dimensionless number that describes how fast light travels through the material. It can be seen as the factor by which the speed and the wavelength of ligh
From playlist Optics: Ray Diagrams, Reflection, Refraction, Thin Lens Equation
Physics 11.2.2b - Index of Refraction
Index of refraction.
From playlist Physics - Reflection and Refraction
Refraction (2 of 5) Snell's Law, Calculating Angle of Refraction and Angle of Incidence
Shows how to use Snell's law to calculate the angle of refraction, the angle of incidence and also to index of refraction. Refraction is the change in direction of a ray of light as it passes from one medium to another. The amount of refraction is determined by the index of refraction of
From playlist Optics: Ray Diagrams, Reflection, Refraction, Thin Lens Equation
Refractive index and Snell's Law measured and explained
The video starts with a reminder of how refraction occurs and moves on the measure the refraction through a perspex block using Snell's Law to measure the refractive index. There is an introduction to refraction here: https://youtu.be/EBTkf07Heq0 explaining how a change in speed of waves
From playlist Light, lenses and mirrors
Physics 11.2.2a - Index of Refraction
Index of Refraction. From the Physics course by Derek Owens. The distance learning class is available at http://www.derekowens.com
From playlist Physics - Reflection and Refraction
Determining the Index of Refraction
Having troubles with your Refraction lab? Let Mr. H help as he explains how to analyze the path of light through a material to determine the index of refraction value. The Snell's Law of Refraction Video Tutorial (referenced on Slide 3) can be found at: https://youtu.be/PUUQk7VPPfQ You
From playlist Refraction and Lenses
Physics - Optics: Refraction (1 of 3) Introduction to Snell's Law
Visit http://ilectureonline.com for more math and science lectures! In this video I will introduce the concepts of light refractions and show you how to find the angle of refraction when a light rays goes from air to water.
From playlist PHYSICS - OPTICS
Physics - Optics: Light Refraction & Snell's Law (2 of 6) Ex. 2 Total Internal Refraction
Visit http://ilectureonline.com for more math and science lectures! In this video I will find the index of refraction using Snell's Law and total internal reflection.
From playlist PHYSICS 52 LIGHT REFRACTION AND SNELL'S LAW
GCSE level Waves covering: Refraction, incident ray, refracted ray, spreading out, total internal reflection, refractive index, endoscope, optical fibre, critical angle, speed of light, snell's law
From playlist GCSE Physics Revision
This physics video tutorial provides a basic introduction into the refraction of light. It discusses the law of reflection and the law of refraction which is also known as Snell's Law. The law of reflection states that the angle of incidence equals the angle of reflection. This video al
From playlist New Physics Video Playlist
Snell's Law & Index of Refraction Practice Problems - Physics
This physics video tutorial provides a basic introduction into snell's law which shows the relationship between the angle of incidence and the angle of refraction given the index of refraction of the two materials. This video explains how to calculate the speed of light of water given the
From playlist New Physics Video Playlist
Can You Believe It? #36 What is Space (5 of TBD) Index of Refraction
Visit http://ilectureonline.com for more math and science lectures! To donate: http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will learn the “bending” of light in space is affected by the index of refraction by a mass like light “bends” when it enters or e
From playlist CAN YOU BELIEVE IT?
Optical Density, Index of Refraction, and the Speed of Light
In this short video from the Refraction and Lenses Tutorial Series, Mr. H discusses the relationship and logic that relates the optical density of a material to the speed of light in that material and to the index of refraction of the material. You can find more information that support
From playlist Refraction and Lenses
26.5 The Dispersion of Light: Prisms and Rainbows
This video covers Section 26.5 of Cutnell & Johnson Physics 10e, by David Young and Shane Stadler, published by John Wiley and Sons. The lecture is part of the course General Physics - Life Sciences I and II, taught by Dr. Boyd F. Edwards at Utah State University. This video was produced
From playlist Lecture 26A. The Refraction of Light: Lenses and Optical Instruments
Physics - Optics: Refracted Surface (3 of 5)
Visit http://ilectureonline.com for more math and science lectures! In this video I will show you how to find the image of an object 50cm away (at the focal point) from the refracted surface.
From playlist PHYSICS - OPTICS