Which of the following is opaque? (1) Water (2) Glass (3) Mirror (4) Prism

Light is a fundamental aspect of our daily lives, and understanding its properties can help us to comprehend how the world around us works. At a basic level, light behaves both as a particle and a wave, a duality that allows it to exhibit characteristics such as reflection, refraction, and diffraction.

When light encounters objects, it can be absorbed, reflected, or transmitted. These interactions with matter determine the visibility, color, and the shadow of objects. Transparent materials, like water and glass, allow light to be transmitted, while opaque materials, like a mirror, reflect it. Understanding these interactions allows us to explain a variety of phenomena, from the colors of a rainbow to the images formed by a mirror.

In the world of optics, transparency and opacity refer to how materials interact with light. A material's ability to transmit light plays a crucial role in how we perceive it. Transparent materials, such as clean water, let nearly all light pass through and are almost invisible when we look through them. In contrast, an opaque object does not allow any light to pass through; it either absorbs or reflects all the light that strikes it.

For example, consider materials like wood or metal; these are opaque because they do not let light permeate them. A transparent material may still distort the light passing through it, while an opaque material like a mirror reflects light, thus enabling us to see our reflection instead of what lies beyond the surface.

Reflection of light is an instance where light bounces off the surface of a material, instead of being absorbed or transmitted. The best example of this is a mirror, which has a highly polished surface causing light to bounce back almost entirely. This bouncing back enables mirrors to form images. The laws of reflection state that the angle at which light hits a surface, known as the angle of incidence, is equal to the angle at which light is reflected, the angle of reflection.

Everyday objects reflect light in a diffuse manner; this means that light is scattered in many directions rather than just one. This is why we can see objects from various angles. Understanding reflection helps us to design better lighting systems and optical devices, like cameras and telescopes, which optimize the way light is captured and used.