TeXes Science Practice Test

Which principle is responsible for the magnification of an object through a lens?

1. Reflection

2. Diffraction

3. Refraction

4. Absorption

The correct answer is: Refraction

The principle responsible for the magnification of an object through a lens is refraction. Refraction occurs when light travels from one medium to another and changes speed, which causes the light to bend. This bending of light as it passes through a lens enables the lens to focus light rays or diverge them, thereby enlarging the image of an object. Convex lenses, for example, are thicker in the center and cause parallel incoming light rays to converge to a point, creating a magnified image. Conversely, concave lenses, which are thinner in the center, spread out light rays, allowing for objects to appear larger when viewed through the lens. Reflection involves the bouncing of light off surfaces, which does not contribute to the magnifying effect provided by lenses. Diffraction is the bending of waves around obstacles and through openings, playing a role in wave behavior but not in the magnification directly through lenses. Absorption relates to materials taking in light rather than allowing it to pass through and create images. Thus, refraction is the key principle behind the magnifying capabilities of lenses.