Does a Magnifying Glass Submerged in Water Still Magnify Objects?

Question:

From water to glass, the change in speed of light is less than from air to glass. Does this mean a magnifying glass submerged in water will magnify?

Answer:

Yes, a magnifying glass submerged in water will still magnify due to the difference in refractive indices. When light travels from one medium to another, its speed changes depending on the refractive indices of the two media. The refractive index of glass is higher than that of air, causing a significant change in the speed of light and resulting in refraction. However, the change in speed from water to glass is relatively smaller. Nevertheless, a magnifying glass works by bending light rays, regardless of the exact speed change. Submerging the magnifying glass in water does not nullify its ability to bend light, so it will still magnify objects by focusing the light passing through it. The change in speed of light alone does not determine the magnification capability of a magnifying glass.

Understanding Refraction and Magnification:

Refraction is the bending of light as it passes from one medium to another, such as from air to glass or from water to glass. The degree of bending is determined by the refractive indices of the two media, which indicate how much the speed of light changes in each medium. When light enters a medium with a different refractive index, it changes speed and angle, causing the familiar phenomena of refraction that we observe in everyday life.

Magnification, on the other hand, is the process by which an object appears larger when viewed through a magnifying glass or lens. This increase in apparent size is achieved by bending light rays to focus them at a specific point, which magnifies the image being viewed. The ability of a magnifying glass to magnify an object is not solely determined by the speed of light in the medium it is placed in, but rather by its design and the way it refracts and focuses light rays.

When a magnifying glass is submerged in water, the change in speed of light from the water to the glass of the lens is minimal compared to the change from air to glass. However, this slight difference in speed does not prevent the magnifying glass from fulfilling its function of bending light rays and magnifying objects. The refractive index of water and glass may differ, but the principle of refraction still applies, allowing the magnifying glass to magnify objects even when submerged.

In conclusion, the speed of light alone does not dictate the magnification capability of a magnifying glass. While the change in speed from one medium to another may vary, the fundamental principles of refraction and magnification remain constant. Therefore, a magnifying glass submerged in water will still magnify objects, showcasing the fascinating interplay between light, refraction, and vision.