This applet demonstrates the special reflective properties of the conic sections: ellipse, parabola, and hyperbola.[br]The green and the blue points are the foci.[br]A source of light positioned in the yellow point emanates radial rays.[br][list][br][*]For each of the conics, move the source yellow point by dragging the “Distance to Foci” slider to one of the foci and away from it. Notice how the rays are reflected.[br][*]For each conics see some applications.[br][/list]

The images are from:[br][url]http://blogs.nejm.org/now/index.php/shock-wave-lithotripsy/2012/07/06/[/url][br][url]http://littlebits.cc/lessons/space-lesson-satellite-dish[/url][br][url]http://www-3.unipv.it/cibra/edu_equipment_uk.html[/url][br][url]http://www.energy-knowledge.net/energy_glossary/solar_cooking.html[/url][br][url]https://en.wikipedia.org/wiki/Cassegrain_reflector[/url]