SOLUTION: A car’s headlight contains a parabolic reflector. A special bulb with two filaments is used to produce the high and low beams. The filament placed at the focus produces the high b

Algebra ->  Rational-functions -> SOLUTION: A car’s headlight contains a parabolic reflector. A special bulb with two filaments is used to produce the high and low beams. The filament placed at the focus produces the high b      Log On


   

Question 853217: A car’s headlight contains a parabolic reflector. A special bulb with two filaments is used to produce
the high and low beams. The filament placed at the focus produces the high beam and the filament
placed off-focus produces the low beam. The equation of the reflector is y=1/12x^2. How far from the
vertex should the filament for the high beam be placed?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
A car’s headlight contains a parabolic reflector. A special bulb with two filaments is used to produce
the high and low beams. The filament placed at the focus produces the high beam and the filament
placed off-focus produces the low beam. The equation of the reflector is y=1/12x^2. How far from the
vertex should the filament for the high beam be placed?
***
y=(1/12)x^2
x^2=12y
Form of an equation for a parabola with vertex at the origin: y=4py
For gven problem:
4p=12
p=3(distance from vertex to focus on the axis of symmetry)
ans: The filament should be placed 3 inches(units?)from the vertex.