Physics I / Problem-Solving: Waves, Fluids, and Thermodynamics
Practice question · Put in order

A power plant boils water with coal, spins a turbine, and lights your lamp. Order the energy conversions, and note where the second law takes its cut.

Hints
  1. Follow the energy: chemical → thermal → mechanical → electrical.
  2. The mandatory waste-heat step belongs where heat becomes work, no engine converts heat completely.
Show the answer
  1. Chemical energy in coal is released as heat by combustion
  2. Heat turns water into high-pressure steam (thermal energy)
  3. Steam expands and does work spinning the turbine
  4. The second law forces part of the heat out through cooling towers
  5. The generator converts rotational work into electrical energy
Why

Every heat engine on Earth follows this chain, and every one pays the second-law toll: heat cannot become work at 100%. The billowing cooling towers are not pollution, they are thermodynamics made visible.

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