Light Electromagnetic waveElectromagnetic wave Needs NO medium to travelNeeds NO medium to travel Transverse wave.Transverse wave. Speed of Light – 3.00 x 10 8 m/sSpeed of Light – 3.00 x 10 8 m/s (In air and in a Vacuum)

Speed of Light ALL electromagnetic waves travel at the speed of light (Radio, TV, Gamma, Ultraviolet and Infrared... See Reference Table)

Dual Nature of Light Light sometimes behaves like a particle Light sometimes behaves like a wave

White Light The light that comes from the sun and other artificial means is called white light or visible light. White Light is composed of the colors of the rainbow.

Visible Light ROY G. BIVROY G. BIV

Light Energy Luminous Objects – Objects that generate their own lightLuminous Objects – Objects that generate their own light Illuminated Objects – Objects that are capable of reflected lightIlluminated Objects – Objects that are capable of reflected light

Light Reflection Regular Reflection Diffuse Reflection

Refraction of Light

Speed of light is dependent on the medium it is traveling throughSpeed of light is dependent on the medium it is traveling through Optical density (Optical density (How well light can pass through)

Index of Refraction Index of Refraction – Number that tells how optically dense an object is based on the speed of light through it.

Index of Refraction Value Ratio of the speed of light in a vacuum to the speed of light in the material.Ratio of the speed of light in a vacuum to the speed of light in the material. n – index of refraction c – speed of light (m/s) v – velocity (m/s)

Snell’s Law As light speeds up, it bends AWAY from the normal As light slows down, it bends TOWARDS the normal

Using Snell’s Law and the values for n in the diagram below, draw arrows to show the path through the layers of different materials.Using Snell’s Law and the values for n in the diagram below, draw arrows to show the path through the layers of different materials. Air (1.0) Flint Glass (1.61) Water (1.33) Diamond (2.42)

Diffraction Bending of a wave around an obstacleBending of a wave around an obstacle Single Slit DiffractionSingle Slit Diffraction

Diffraction Double Slit DiffractionDouble Slit Diffraction

Diffraction Size of opening and wavelength affect the diffraction pattern Greatest diffraction pattern occurs with a long wavelength and narrow opening

Polarization Unpolarized light – Light waves which are vibrating in more than one plane (Sun, lamps, candle)Unpolarized light – Light waves which are vibrating in more than one plane (Sun, lamps, candle) Polarized Light – Light waves in which the vibrations occur in a single planePolarized Light – Light waves in which the vibrations occur in a single plane

Polarization Polarization – process of transforming unpolarized light into polarized light.Polarization – process of transforming unpolarized light into polarized light. Uses - SunglassesUses - Sunglasses

WARM-UP The speed of light in Lucite is _________? The speed of light in goop is 2.56x10 8 m/s. What is the index of refraction of goop?

Lab #17 and #18 Lab #17Lab #17 –Problem: How are the angle of incidence and the angle of reflection related? Lab #18Lab #18 –Problem: How are the angle of incidence and the angle of refraction related?