On the other hand, E-beam sterilization can be harmful to products containing batteries or electronic components. It can also degrade rubber and polypropylene, but these materials now come in grades that are E-beam compatible, Wilson notes.
A trajectory is the path of an object through space, or the path of life that a person chooses. The prefix tra- is short for trans-, which means across (think transport and transit) and the ject comes from jacere, which means throw and is also the root of the word jet.
Geometric Definition. Definition: A parabola is the set of points in the plane that are equidistant from a point (the focus) and a line (the directrix.). The following exercise should help convince you that this definition yields the parabolas you are familiar with. Exercise: Given a focus at (0,1) and a directrix y=-1, find the equation of the parabola. How to do it: draw a figure showing a generic point P on the parabola, with coordinates (x,y).