A low temperature Stirling engine placed over a cup of hot water runs as heat flows from the water to the engine, demonstrating energy conversion from heat to mechanical motion.

1. Pour hot water into a coffee cup.
2. Place the low temperature Stirling engine on top of the cup.
3. Wait about 15 seconds to allow the engine to warm up.
4. Gently spin the flywheel to start the cycle.
5. Observe as the engine continues to run using heat from the hot water.

An Elegant Machine - The Stirling Engine - ScienceOnline:

Stirling Engine Demo - Physics Demos:

📄 Low Temperature Stirling Engine - UCSC Physics Demonstration Room: https://ucscphysicsdemo.sites.ucsc.edu/physics-5b6b-demos/low-temperature-stirling-engine/

• Use different water temperatures to test how heat input affects engine performance.
• Try placing the engine on ice water to see if it can run in reverse from a cooler source.
• Compare performance using different sized cups or containers to change heat transfer rates.

• Handle hot water carefully to avoid burns.
• Place the cup on a stable surface to prevent tipping or spilling.
• Do not touch moving parts of the engine while it is operating.

• Why does the engine need an initial push to start? (The flywheel requires motion to overcome inertia and begin the repeating cycle.)
• What is the energy source that keeps the engine running? (Heat energy from the hot water is converted to mechanical energy.)
• How do the four steps of the Stirling cycle relate to the observed motion? (Heating, expansion, cooling, and compression of the working gas keep the piston and flywheel moving.)
• How does this experiment illustrate real-world applications of heat engines? (It models principles used in power generation and alternative energy devices.)