Stream of Fire ?

This photograph is not a picture of a stream of fire, nor is it an explosion of magma. The photograph is actually a picture of an ordinary kitchen sink and a streamof water. The sink is set up so the laser beam passes through the back of the clear jug of water to the hole cut in the front of the jug. The water falls out of the jug following a parabolic trajectory. The laser beam is ‘trapped’ inside the falling streamof water because of total internal reflection. Total internal reflection occurs when the light is in a more dense medium (the water), is heading towards a boundary with a less dense medium (the surrounding air), and the angle of incidence is greater than the critical angle for the dense medium. This physics concept is being applied in the growing field of fiber optics.

Matthew Sorbarra and Marc Settino
St. Elizabeth Catholic High School, Richmond Hill, Ontario
Honourable Mention ( HS Individual Category )
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