Thermal Physics : The Game Changer

Thermal Physics is one of  those units in Physics that is sure to act as your masterstroke during exams, if worked on properly. 


Well, HEAT being a form of energy is something with which we are surrounded every time The practical applications of this unit are very wide. From heating up your pizzas to the melting of ice in Arctic and the various instruments like thermoscopes, thermometers, thermograms, etc that are governed by the temperature and radiation. Do you know about infrared radiation? An instrument thermogram gives colour-coded heat content of any body – white and red indicating the greatest radiation rate. You must have seen it on the Discovery Channel. Well, it is interesting to note how temperature can be judged from the radiations from a body. HEAT can be transformed, transferred and absorbed. The more you explore about it, the more interesting its study gets.


  • Heat flow can be made easy by taking heat flow analogous to current flow in electricity and coefficient of thermal conductivity analogous to resistivity. I’m sure your physics teacher might have taught you this. To those who ignored it finding it inappropriate to complicate heat with electricity, trust me, this method is way too useful.
  • KTG – A very very important part. Be thorough with NCERT. Minute pieces of info like, dependency of mean free path on pressure or temperature can be asked…be prepared ! 
  • RADIATION LAWS  – Stefan’s law, Wien’s displacement law and topic such as emissive  and absorbtive powers of black body are important topics you should know. Many questions can be solved if you know the definitions of these terms clearly.
  • THERMODYNAMIC PROCESSES – This one is a simple yet highly logical topic. You should maintain a good grip over all the processes along with the graphical relations. Graphs are something most frequently asked by JEE under this section.
  • Latent heat, Specific heat at constant pressure and Specific heat at constant volume forms an important part. After this comes the degree of freedom part. All this is pretty easy if you have done it already in Chemistry.

However, focus should be on how questions are framed using these sectionsFor example,paper setters basically mix the concept of specific heats of monoatomic or diatomic gas with the thermodynamic process taking place with the gas. Easy…..right? Only if you are clear with the basics. Memorizing the formulae will only help you for JEE Main but it is the concepts coupled with inense practice that will sail you through JEE Advanced.

WHAT IF I KNOW ALL THE CONCEPTS YET FAIL TO APPLY THEM IN TRICKY QUESTIONS?  …I would say…..Practice and practice more till you are finally able to attempt the previous years’ questions easily and accurately( the latter being more important 🙂 ). There is a high probability that you end up making SILLY MISTAKES or ignoring subtle small but relevant points.

BOOKS: If you are good with thermal physics, good as in if you are able to solve any question from this section without making mistakes and  given any new question, you are able to think of the concept to be applied; follow HC Verma-II and NCERT. …If you feel a need to prepare more, then go solve I.E. Irodov : Problems in General Physics.

12 thoughts on “Thermal Physics : The Game Changer”

  1. This was really helpful. now i know exactly what to study in thermal physics. Can you please post a similar blog for coordinate geometry?

      1. This was written at the end , so in response with the last 2 paragraph I have requested Integral Calculus :-

        ALRIGHT Friends, so this was all about Thermal Physics. Now, you as a reader of this blog, are most welcome to put forward your point of view, like if you want guidance with some SPECIFIC PART of this unit.

        Plus, it would be really nice at your part if you participate and let us know what other topics or subjects you are looking forward to be helped with. It would be appreciated.


        Shaivy Adhikari (1st year undergrad, IIT Roorkee)

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