parabola equation

Question

A spotlight uses a parabolic reflector, a surface with a parabolic cross section, and a light bulb at the focus of the parabola. If the bulb is 5.5 inches from the vertex of the reflector, what is the equation of the parabola? Explain your reasonin

Answer 1

Hello Derek,

The concept for this problem is the same as your previous question. That is, you can use the equation

y =(1/(4p))x².

Here, p = 5.5, and so the equation of the parabolic cross section of the reflector may be written as

y = (1/22)x².

William