"**The first law of thermodynamics states that no energy is ever lost during conversions**: be that chemical to chemical when digesting food; chemical to mechanical when moving muscles; chemical to thermal when burning natural gas; thermal to mechanical when rotating a turbine; mechanical to electrical in a generator; or electrical to electromagnetic as light illuminates the page you are reading. **However, all energy conversions eventually result in dissipated low-temperature heat: no energy has been lost, but its utility, its ability to perform useful work, is gone** (the second law of thermodynamics)." ([Location 622](https://readwise.io/to_kindle?action=open&asin=B08SGC3TD3&location=622)) --- **Tags** -- [[quotes]], [[thermodynamics]], [[conservation-of-energy]], [[entropy]], [[energy-conversion]] **Source** -- [[202412030828 - B - How the World Really Works]]