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The Challenge: Make distilled water from seawater using solar power

What is so special about the parabola shape?

The parabola has a very well defined mathematical formula. If we draw a graph with the y axis going up the page, the x axis across the page and a being the distance of the focus from the mirror, the shape of the parabola is plotted out by the formula y2=4ax and forms a C shape.

Graph animation