Which of the following is a solid?

Matter exists in different states, primarily solid, liquid, and gas. Each state has distinct characteristics based on the arrangement and movement of particles. In a solid, particles are tightly packed in a fixed structure, giving solids a definite shape and volume. Liquids, on the other hand, have a definite volume but no fixed shape, while gases have neither a fixed shape nor volume.

In this question, the substances given are water and stone. Water is a liquid at room temperature, which flows and takes the shape of its container. Stone is a solid, composed of tightly packed particles, giving it a rigid structure and maintaining its own shape.

The option “Both” is incorrect because water does not qualify as a solid under normal conditions. Similarly, “None” is incorrect because stone is clearly a solid. Understanding these distinctions is fundamental in Physics, as it helps explain concepts like density, pressure, melting, and freezing.

Solids like stone have many practical applications: they form buildings, tools, and natural structures. By contrast, liquids like water are essential for life and can flow into containers of any shape. Recognizing solids in everyday life helps students understand how particle arrangement affects material properties.

This knowledge is part of the fundamentals of matter, forming the basis for studying more complex topics in thermodynamics, material science, and chemistry. Observing solids in the environment, such as rocks, metals, and wood, provides a practical understanding of how matter behaves in different states.