Suppose you wanted to start a fire using a mirror to focus sunlight.Which of the following statements is most accurate?
A)It would be best to use a plane mirror.
B)It would be best to use a convex mirror.
C)It would be best to use a concave mirror,with the object to be ignited positioned at the center of curvature of the mirror.
D)It would be best to use a concave mirror,with the object to be ignited positioned halfway between the mirror and its center of curvature.
E)One cannot start a fire using a mirror,since mirrors form only virtual images.

Question

Quizplus · Accepted Answer

A concave mirror is the best choice for focusing sunlight to start a fire because it can converge the light rays to a single point, known as the focal point. If the object to be ignited is positioned at the focal point, the concentrated light energy will heat it up enough to start a fire. However, the object needs to be positioned halfway between the mirror and its center of curvature to get the most intense heat. This is because the focal point lies precisely at the center of curvature for a concave mirror, which makes the light rays converge with the greatest intensity at a point halfway between the mirror's surface and its center of curvature.

Suppose You Wanted to Start a Fire Using a Mirror