Question

Car headlights use concave mirrors. There's a concave mirror in the back of the headlight socket, and the actual light bulb is placed somewhere along the principal axis. Your question for this essay: where should that bulb be placed for the best headlight design? Should it be at the focal point? At the radius of curvature? Somewhere else? Explain your answer.

Answer 1

Answer:

At the focus

Explanation:

In car head lights concave mirrors are used. The light bulbs in these headlights are place along the principal axis  as shown in the figure. On this Principal axis light bulbs are place at the Focus to get maximum brightness. As from the figure we can conclude that light rays coming from infinity converse at focus thus, giving maximum brightness.