Physicist and inventor — Jacques Alexandre César Charles (Beaugency, 1746 – Paris, 1823) was a French physicist, chemist and inventor, a member of the Academy of Sciences. Around 1787 he observed that, at constant pressure, the volume of a gas increases proportionally with temperature, a relationship now known as Charles’s law, one of the foundations of the study of ideal gases. Although he did not publish this result, it was later taken up and made known by Gay-Lussac. Charles was also a pioneer of aerostatics: in 1783 he designed and piloted one of the first hydrogen-filled balloons, competing with the Montgolfier brothers, who used hot air. His contributions link the physical study of gases to humankind’s earliest ventures into flight.

Theories and contributions

  • Charles’s law — At constant pressure, the volume of a gas is proportional to the absolute temperature: VT=constant\dfrac{V}{T} = \text{constant}.

Linked atoms

1 linked atoms.

09 Teoria cinetica dei gas