Introduction to Thermodynamics

Thermodynamics is the branch of physics that studies heat, energy, and the ways they move from one place to another. It deals with how energy changes form, how it flows, and how it affects matter.

Instead of looking at individual atoms or molecules, thermodynamics focuses on the overall or macroscopic behaviour of systems.

Many natural processes around us—from boiling water and running engines to melting ice and weather formation—are governed by thermodynamics. It helps explain why heat flows the way it does and why some energy conversions are possible while others are not.

Thermodynamics connects physical quantities like heat, work, pressure, volume, and temperature to understand how systems behave.

Thermodynamics takes a macroscopic view, meaning it looks at large-scale properties like temperature, pressure, and volume. It does not follow each particle separately.

This approach makes it easier to analyse systems without worrying about the motion of every molecule.

Thermodynamics focuses on changes in:

• Heat: energy transferred because of temperature difference
• Work: energy transferred when a force moves something
• Internal energy: total microscopic energy of a system

It also studies how these quantities interact during processes like expansion, compression, heating, or cooling.

Temperature is a key concept in thermodynamics. It determines the direction of heat flow and tells us about the energy of particles inside a system.

Thermodynamics uses temperature to define equilibrium and to describe interactions between systems.

Thermodynamics plays a major role in science, engineering, and everyday life. It helps us understand how machines work and how natural processes behave.