Chapter+22+Refraction

Chapter 22 Refraction Cameron Ruhl Equations: 1) 2)

3) 4) 5) 6) Vocab: Dual Nature of Light- light behaves under properties of both waves and particles Reflection- the bouncing of a ray of light off of a smooth medium Refraction- the bending of light passing into a medium through an angle relative to the perpendicular normal line to the medium's surface Ray approximation- the assumption of light to appear as straight line waves, given by the experience of light traveling in a straight line path in a homogerneous medium until it encounters a boundary between two mediums Wave front- a surface passing through the points of a wave that have the same phase and amplitude Specular reflection- the reflection of light off of a smooth surface Diffuse reflection- the reflection of light off of any rough, uneven surface Angle of refraction- the angle to the normal line through which light is bent when passing through a medium Index of refraction- the ratio of the speed of light in a vacuum to the speed of light through a medium Dispersion- the dependence of the index of refraction on wavelength angle of deviation- the angle a beam of light is bent through as it exits a prism Visible Spectrum- the array of colors of visible light according to the wavelength of the light ray Prisim Spectrometer- instrument used to seperate the light into its different wavelengths. Huygen's Principle- all points on a given wave front are taken as point sources for the production of spherical secondary waves, called wavelets, that propagate in the forward direction with speeds characteristic of waves in that medium. After some time has elapsed, the new position of the wave front is the surface tangent to the weavelets. Critical angle- the angle at which the refracted ray of light will moves parallel to the boundary so that the angle of refraction will equal 90, all angle above this angle will result in entirely and internally reflection of the ray Example Formula problems: 1) A ray of light enters from air into a medium with an incident angle of 45 __degrees__ from air and refracts through an angle of refraction of 30degrees. What is the index of refraction of the medium? 2) A ray of light is traveling through a vacuum with a wavelength of 600nm, how much energy does a photon of this ray have? 3)What is the velocity of a ray of light having a 550nm wavelength and a frequently of 4x10^14 Hz? 4) A ray of light passes through a medium at 1.7x10^8 m/s, what is the medium's index of refraction? 5) Light enters from air into a diamond with index of refraction of 2.46, what is the diamonds critical angle? 6) A ray of light hits a smooth surface at an incidence angle of 36 degrees, what angle does it leave at? Video: [|Reflection of light demonstration] Multiple Choice: 1)The frequency of a ray of light does what when it enters a medium in refraction? a. remains the same b. changes while in the medium and reverts back to what is was before it entered c. changes in the medium and remains the same when it leaves d. oscillates within a specific range 2)The difference between diffuse and specular reflection is? a. diffuse is caused by light from a light bulb and specular from a laser b. in diffuse reflection some of the light is refracted and in specular it is not c. diffuse occurs on an uneven, rough surface and specular on an even, smooth one d. specular only occurs on solids and diffuse on liquids 3) An incident ray of light hits a surface at 35 degrees to the normal and is refracted, what is its angle of refraction if the medium's index of refraction is 1.68? a. 20 degrees b.14 degrees c.67 degrees d. 44 degrees 4) A ray of light strikes a medium at 67 degrees to the normal, if the angle of refraction is 27.1 degrees, how fast is the light travelling when it leaves? a.1.9e8 m/s b.1.49e8 m/s c.2.6e8 m/s d.2.91e8 m/s 5) What is the critical angle of the above medium? a. 29.7 degrees b. 44.2 degrees c. 18.4 degrees d. 25.1 degrees Answers 1)a 2)c 3)a 4)b 5)a