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3 ideas
20645 | Heat is a state of vibration, not a substance [Joule] |
Full Idea: We consider heat not as a substance but as a state of vibration. | |
From: James Joule (works [1870]), quoted by Peter Watson - Convergence 01 'Nature's' | |
A reaction: The puzzle is that giving accurate accounts of vibrations, heat and movement require a quantitative substance, energy. But all we have here is movement, and the denial of a substance. Energy is 'nature's currency system'. |
20972 | Joule showed that energy converts to heat, and heat to energy [Joule, by Papineau] |
Full Idea: James Joule established the equivalence of heat and mechanical energy, in the sense of showing that a specific amount of heat will always be produced by the expenditure of a given amount of energy, and vice versa. | |
From: report of James Joule (works [1870]) by David Papineau - Thinking about Consciousness App 4.2 | |
A reaction: This was a major step towards the law of conservation of energy. |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |