I got into a debate with a friend about the meaning of physics and its purpose, he is the sort who will test you and if you get it wrong it somehow gratifies his own self-reflection and self-worth. That aside, I have loved physics since I got into it when I was at school, I had a great teacher who fostered that love and helped grow my appreciation for physics and ever since I have said to myself that I would one day go do my degree in physics. At the moment I have just finished my degree in computer security and forensics, I plan to study physics part-time hopefully in the next 5 years after I settle into permanent work in the software engineering field.

Anyway the conversation started with a question from him asking what temperature water boils at and what temperature does water freeze at. For the life of me I couldn't remember, even as a general question most would know the answer, well that's what we thought. For him this was a big disgrace and he continued to laugh and "then" call a friend to verify that I am being moronic. Of course he phoned our friend and pitched the same question, of which he neither knew the boiling point nor the freezing point of water. Regardless, for him he classed this as "true physics", but to me it could have been any random number for all I cared.

What he was trying to prelude to and was expecting as an answer was "it depends" and the dependency was altitude (from a documentary he watched). Of course I never got past that stage and all it became was a ridicule session. For me it didn't matter I thought the true physics was understanding why water boiled in the first place. How exciting molecules or increasing the energy within water gradually increases its temperature and when the molecules become extremely excited water gets to its boiling temperature. Understanding this allows us to understand all the states of water (phases), from a solid (ice) to a liquid or to a gas (vapour, altho vapour is essentially two phases) in one, the phase change occurs via nucleation and growth - small liquid drops spontaneously form and evaporate, but if a drop is larger than some critical radius, it will continue to grow ('nucleates'). This is the most common phenomenon of a gas-liquid (or liquid-solid) phase transition. Of course I discussed this with him but he argued blind that "knowing" the boiling point of water was "physics" but to me that was essentially just a factoid. That the boiling point of water did not matter but understanding the process behind it did.

So I ask those of you in the community who was wrong or what physics trully is.

If we take the standard definition of Physics it is a natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.

For me knowing the boiling temperature of water does not equate to understanding how water as a liquid, boils. Or the transfer of energy to change a liquids state occurs. It is simply just a consequence of the action or a "factoid" of the means in which we can reliably get the same testable results.