Which of the following is translucent? (A). Ground glass (B). Wood (C). Stone (D). Plastic
Hint: You can start by explaining what opacity of material means. Then state the classification of objects according to the level of opacity (opaque, translucent, and transparent). Then mention which of the given options is a translucent material.
Complete step-by-step answer: In this problem, we are dealing with the opacity of the material. Opacity refers to the extent to which an object allows the light to pass through it. There are 3 major levels of opacity according to how much light passes through the object: Opaque objects – Opaque objects do not let any light pass through them. Some examples of opaque objects are wood, stones, soil, plastic, etc. Transparent objects – These objects allow all the light to pass through them. These materials do not absorb any percentage of the light. Some examples of transparent objects are clean water, glass, etc. Translucent objects – The nature of these objects is in between opaque and transparent objects. They allow the light to pass through but only to some extent. When light passes through translucent objects some of the light is absorbed and some of the light is reflected. Some examples of translucent objects are ground glass (also called frosted glass), butter paper, etc. So, among the following options wood, stone and plastic are opaque objects, only ground glass is translucent. Hence, option A is the correct choice.
Note: – In the solution we mentioned above we discussed how transparent objects do not absorb any light. But in reality no matter how transparent the object appears, whether it be clear glass or clean water, they do absorb a very light amount of light. But it is so small, it is generally ignored.