Post on 12-Jun-2015
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PowerPoint Handouts for Tyndall Effect
Tyndall Effect is often seen from the dust in the air It
when sunlight comes in through a window, or comes down through holes in clouds.
Tyndall EffectAn Irish Scientist named John Tyndall discovered that light bounced off of tiny particles in the air and in liquids. This scattering of light became known as the Tyndall Effect
In liquids the tyndall effect can be easily seen by using a laser pointer. If you dilute milk to where it is almost clear, or if you have any type of sol, such as colloidal silver, then the beam of the laser can be easily seen as it travels through the liquid.
Tyndall Effect caused by reflection of light by very is
small particles in suspension in a transparent medium.
Tyndall EffectThe glass on the left contains 5 ppm of HVAC colloidal silver and the one on the right is from the tap after the bubbles have settled out.
Raleigh scattering is proportional to the inverse fourth power of wavelength, which means that the shorter the wavelength of blue light will scatter more than the longer wavelength of green and red light.This gives the sky a blue appearance.
Why thesky is blue ?
Conversely, when one looks towards the sun at sunset, one sees the colors that were not scattered away --- the larger wavelength, red light.
When one looks at the sky, rather than seeing the black space, one sees light from Raleigh scattering off the air.