the interaction of light and matter reflection and refraction of light 11-12 light can do three...
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The Interaction of Light and Matter
Reflection and Refraction of LightReflection and Refraction of Light
11-1211-12
• Light Can do Three Things:
• 1) Absorb
• 2) Transmit or Refract
• 3) Reflect
Absorption, Transmission, and Reflection
The Interaction of Light and Matter
Reflection and Refraction of LightReflection and Refraction of Light
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• The opaque material in this candleholder only absorbs and reflects light—no light passes through it.
Absorption, Transmission, and Reflection
• Materials that allow some light to pass through them, are described as translucent.
Absorption, Transmission, and Reflection
Reflection and Refraction of LightReflection and Refraction of Light
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Absorption, Transmission, and Reflection
Reflection and Refraction of LightReflection and Refraction of Light
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• Transparent materials, such as this candleholder transmit almost all the lightstriking them, so you can see objects clearly through them.
Reflection of Light
Reflection and Refraction of LightReflection and Refraction of Light
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• A smooth, even surface such as a pane of glass produces a sharp image by reflecting parallel light waves in only one direction.
Regular and Diffuse Reflection
• Reflection of light waves from a smooth surface is regular reflection.
• To cause a regular reflection, the roughness of a surface must be less than the wavelengths it reflects.
• Ex: LOOKING IN A MIRROR
Regular and Diffuse Reflection
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• Diffuse reflection is a type of scattering that occurs when light waves traveling in one direction are made to travel in many different directions.
• Ex: white cloth
• Reflection of light from a rough surface is diffuse reflection.
Refraction of Light
Reflection and Refraction of LightReflection and Refraction of Light
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• Refraction is caused by a change in the speed of a wave when it passes from one material to another.
Refraction of Light
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• Index of refraction is the ratio of the speed of light in a vacuum to the speed of light in the material.
• The index of refraction indicates how much the speed of light is reduced in the material compared to its speed in empty space.
• The larger the index of refraction, the more light is slowed down in the material.
Refraction of Light
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• White light, such as sunlight, is made up of light waves with range of wavelengths.
• Prisms refract the light twice—once when it enters the prism and again when it leaves the prism.
Refraction of Light
Reflection and Refraction of LightReflection and Refraction of Light
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• The longer wavelengths of light are slowed less and are bent the least.
• As a result, the different colors are separated when they emerge from the prism.
Diffraction of Light (10-3)
Reflection and Refraction of LightReflection and Refraction of Light
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• Occurs when an object causes a wave to change direction and bend around it.
• The amount of diffraction that occurs depends on the size of the object
• If the object is smaller than the wavelength then the wave will bend around it
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