Thermodynamics

Joule's Experiment

[M | t++ | —]
Falling mass turns paddle wheel in honey raising its temperature.

Bag of Lead Shot

[M | t | ★]
Dropping bag containing lead turns gravitational potential energy to heat.

[In-Depth Description]

Friction Heating

[M | t | —]
Boy scout trick, rubbing metal rod with rope heats rod.

Adiabatic Heating with Syringe

[S | t+ | —]
Compression of gas within syringe heats gas and ignites cotton.

Adiabatic Heating

[M | t+ | ★]
Compression of gas within bicycle pump heats gas; alternatively, syringe PV=nRT (w/ Mac TC read-out).

[In-Depth Description]

Stirling Cycle Engine

[M | t+ | —]
Hot air external combustion engine.

Vortex Tube

[M | t++ | —]
This clever tube separates hot and cold air out of a jet of room temperature air and serves as a refrigerator.

[In-Depth Description]

Maxwell's Demon

[M | t | —]
Black and white balls, rolling around in a glass flask, are seemingly segregated by Maxwell's demon to decrease entropy.

Thermoelectric Motor

[S | t+ | —]
Two different temperature heat reservoirs power the motor - it's not how hot it is that counts but rather the temperature difference.

Steam Engine

[M | t+ | —]
Small steam engine to drive external dynamo and lamp.

Archibald Rubber Band Engine

[M | t+ | —]
Differential expansion and contraction of rubber bands turns wheel half-immersed in hot water.

Increasing Entropy

[M | t+ | —]
Two, sealed, connected, glass flasks contain smoky air and a vacuum respectively; opening the connecting valve increases the entropy of the system.

Videotape Entropy

[M | t+ | —]
Watch entropy increase with repeated re-recordings.

Mixing and Unmixing

[M | t+ | ★★★]
Food coloring in glycerine is mixed by turning a drum, then unmixed by reversing. Has entropy decreased?

[In-Depth Description]

Contact Us

Mailing Address: Lecture Demonstration Services, Science Center, Rm B-08A, 1 Oxford Street, Cambridge, MA 02138
Campus Location: Science Center B-08A | Tel: (617) 495-5824 | Email: scidemos-at-fas.harvard.edu