Heat, Work or Energy?
Today is the birthday of James Prescott Joule, born on December 24, 1818 in Salford, Lancashire, for whom the joule is named (symbol J) which is a derived unit of energy, work, or amount of heat in the International System of Units. Tutored at a young age by no less than John Dalton and collaborator of Lord Kelvin, Joule’s work is fundamental to our understanding of work and energy, discovering the relationship between heat and mechanical work, which led to the First Law of Thermodynamics. Because of this relationship, a joule can be defined many ways: a joule is equal to the energy transferred when applying a force of one newton through a distance of one meter (1 newton meter or N·m). A joule is equal to passing an electric current of one ampere through a resistance of one ohm for one second. A joule is equal to the energy required to accelerate a 1 kg mass at 1 m·s−2 through a 1 m distance in space. In short, a joule is a way to understand the relationship between heat, work and energy! Happy Birthday to James Prescott Joule!
