I How did Charles obtain his law when absolute temperature wasn't define

AI Thread Summary
The discussion revolves around the understanding of temperature measurement, specifically the relationship between Charles's Law and the absolute temperature scale established by Lord Kelvin. The user expresses confusion about how Charles's Law, formulated in 1780, can be referenced in the context of the Kelvin scale, which was developed in 1848, particularly regarding the concept of absolute zero at -273.15°C. Responses suggest exploring historical thermodynamics through a video playlist for clarity. Additionally, a Wikipedia link is provided to further explain Charles's Law. The conversation emphasizes the importance of understanding the foundational concepts in thermodynamics to resolve these doubts.
Ahsan Khan
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The Kelvin temperature (T) was not introduced during the time of Charles, so there was no definition of absolute temperature T during that time how then Charles Proposed that at constant pressure Volume (V);of gas is directly proportional to it's absolute temperature T( V/T= constant) ?
Hi all

These days I am refreshing my knowledge on the concept and measurement of temperature. One way of defining temperature is in terms of how it is measured. This can be done by observing the variation of some properties which vary linearly with the hotness(temperature) of bodies. I studied about Celsius scale, Fahrenheit scale no problem. But when I come to study absolute scale few questions and doubts arises in my mind.

One of doubts is that Charles brought his law in 1780 and the absolute temperature scale by Lord Kelvin came is 1848 right? Now in introduction to Kelvin scale they are referring Charles Law and Boyles Law and use PV=nRT, to arrive at the fact that their is some minimum possible temperature and if we extrapolate the(pressure temperature) P -T graph graph then that minimum temperature is -273.15°C. Which is known to be Zero Kelvin.

This doesn't make sense to me because without Kelvin Scale we should not talk about Charles law at the first place. I must missing something. Any help will be highly appreciated!

Thanks a bunch:)
 
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This series of videos explores the history of thermodynamics theory. Perhaps one of them may have the answer you seek. I put the playlist link in code tags to prevent the PF software from converting it to a link to a single video.

Paste this link into your browser.
[CODE title="Html"]
https://www.youtube.com/playlist?list=PLepnjl2hm9tHRMTdVyJ8t9HB6TZ63hFdU
[/CODE]
 
anorlunda said:
This series of videos explores the history of thermodynamics theory. Perhaps one of them may have the answer you seek. I put the playlist link in code tags to prevent the PF software from converting it to a link to a single video.

Paste this link into your browser.
[CODE title="Html"]
https://www.youtube.com/playlist?list=PLepnjl2hm9tHRMTdVyJ8t9HB6TZ63hFdU
[/CODE]
Video topics look relevant. Start watching them. Will respond after watching.

Thanks anorlunda
 
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