Stirling Engine Runs from Heat Difference

Engine continues running with no battery. Ask students to predict what will happen. Place engine on warm source and spin flywheel gently. Key idea: A temperature difference drives expansion/contraction of trapped gas, converting heat to work. Ask: What is the 'fuel' if nothing is burning? Safety and cleanup: Warm water only; keep fingers out of flywheel. https://physics.wvu.edu/internal/lecture-demonstrations/thermodynamics