Why does a magnifying glass under water magnify less?

Why does a magnifying glass under water magnify less?

A magnifying glass under water will magnify less. This is due to differing refractive indices of glass and water causing distortion. Magnification is also influenced by lens focal length and resolving power.

Refractive Indices and Distortion

Refractive indices refer to how much light is bent (or refracted) when passing from one medium to another. Glass and water have different refractive indices, causing the light path to change when the magnifying glass is submerged in water. This difference in refractive indices between glass and water leads to distortion of the object being viewed through the magnifying glass, resulting in less magnification.

Lens Focal Length

Lens focal length is another factor that affects magnification. Lenses with shorter focal lengths have greater angular magnification. When a magnifying glass is placed under water, the change in the light path due to the different refractive indices can alter the effective focal length of the lens, affecting the magnification of the object.

Resolving Power

Resolving power is the ability of a lens to distinguish between small details. While magnification is about enlarging an image, resolving power is crucial for discerning fine details. The distortion caused by the refractive indices of glass and water can impact the resolving power of the magnifying glass under water, further contributing to the reduction in magnification.