Question

check my answer please?
A cars 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= 1/12 x^2. How far from the vertex should the filament for the high beam be placed?

Answer 1

y/x^2/(4a)

Answer 2

a=3

Answer 3

so it should be 3 units away from the vertex???

Answer 4

@phi can you help ??

Answer 5

yes, that sounds correct. You want the light at the focus (because when the light hits the parabola it bounces off in a special way.