Bild

Siemens Stiftung

Pump storage plant with surplus in the grid

Graphic:
Functional diagram pump storage power plant with a surplus in the electric power grid.

When there is excess electricity in the electricity grid, an electric pump in the plant is used to pump water from a lower tank to a higher one.
Note: During spikes in demand, the water flows back down from the higher tank through the turbine of the low-lying power plant.

Medientypen

Bild

Lernalter

16-18

Schlüsselwörter

Hydroelectric plant Power generation

Sprachen

Englisch

Bild

Siemens Stiftung

Phase diagram of water

Diagram:
A P-T diagram for pure water. The lines indicate the temperature and the pressure at which the solid, liquid, and vapor phases exist in equilibrium. All three phases exist in equilibrium only at the triple point; otherwise, there are a maximum of two phases.

In addition to the equilibrium curves (melting pressure curve, sublimation curve, vapor pressure curve), the diagram also includes the pressure and temperature data for the melting, boiling, triple, and critical points.
Attention: The axes of the diagram are not shown true to scale.

Information and ideas:
This diagram also reflects the density anomaly of water (lower density in the solid state than in the liquid state): The melting pressure curve shows a negative slope. The reason for the density anomaly is the hydrogen bonds.

Bild

Siemens Stiftung

Microphone - transparent

Graphic:
With a moving coil microphone (dynamic microphone), the coil moves in "time" with the sound and produces a tone-frequency current.

In a microphone the mechanical energy of the sound waves is transduced into electric energy. From the mechanical vibrations the microphone produces an electric signal of the same frequency and amplitude.

Information and ideas:
Explanation of the process of sound transduction as it occurs in the inner ear of a human being using a technical device familiar to the students.

Relevant for teaching:
Sound/acoustics: parameters
Communication and understanding
Vibrations and waves

Bild

Siemens Stiftung

Guitar, a classical string instrument

Photo:
Sound is produced by plucking strings and their vibrations are reflected by the resonance of the guitar body.

The vibration of the strings is transmitted to the body (soundboard) of the guitar which in turn vibrates and stimulates the air in the hollow body to vibrate itself. Finally a much bigger volume of air is now vibrating, the sound of the strings is much more clearly audible.

Information and ideas:
Guitar, violin and piano are good examples to illustrate the production of sound through vibrating objects on the one hand and, on the other hand, to show the importance and function of resonance bodies.

Relevant for teaching:
Acoustic phenomena
Sound/acoustics: parameters
Vibrations and waves

Bild

Siemens Stiftung

The Ear, Hearing and Hearing Impairment: Differentiated frequency ranges in the cochlea

Labeled graphic:
Position of the receptors for tones of varying frequencies in the spiral canal of the human cochlea.

Frequencies between 16 hertz (hertz = vibrations per second, abbr.: Hz) and 20,000 Hz can be heard by the human ear.
To differentiate these frequencies, the receptors for high tones are at the beginning of the canal, those for the low tones at the apex of the cochlea.

Information and ideas:
The illustration is suitable for explaining or revising fundamentals of Physics like sound, frequency and vibrations.
Usable in a worksheet, for work together on the digital projector, or as an overhead transparency.

Further information regarding this graphic is available on the media portal of the Siemens Stiftung.

Relevant for teaching:
The human body
Structure and function of a sense organ
Perception of sound
Human hearing ability
Communication and understanding

Bild

Siemens Stiftung

Color mixing with light-emitting diodes

Photos:
Colors can be generated according to the additive color mixing process even with two unregulated colored LEDs.


Colors can be generated according to the additive color mixing process even with two unregulated colored LEDs.

Information and ideas:
Precise instructions and teaching ideas for building a variable LED color mixer can also be found on the media portal of the Siemens Stiftung.

Medientypen

Bild

Lernalter

11-18

Schlüsselwörter

Color Theory Light Semiconductor

Sprachen

Englisch

Bild

Siemens Stiftung

Gießkanne als Trompete

Foto: Kind bläst in eine Gießkanne. So lassen sich relativ laute trompetenartige Töne erzeugen.Durch den zwischen den Lippen ausgepressten Luftstrom wird die Urschwingung erzeugt. Zusätzlich wird das gesamte Luftvolumen in der Gießkanne zum Mitschwingen angeregt: Der Ton wird lauter. Bei bestimmten Tonhöhen schwingt das Kannenvolumen stärker bzw. schwächer mit. Da in unserem Fall bevorzugt die tiefen Töne mitschwingen, klingt die Gießkannentrompete relativ dumpf. Hinweise und Ideen:Leichter Versuch zum Nachmachen. Dann können Parallelen gezogen werden zu diversen Musikinstrumenten, die genau dieses Prinzip nutzen.Unterrichtsbezug:Schall/Akustik: KenngrößenSchwingungen und WellenAkustische Phänomene

Bild

Siemens Stiftung

Geigenkorpus als Resonanzkörper

Foto:Die allseits bekannte Geige als Beispiel, wie die Schwingung einer Saite erst über einen Resonanzkörper auf Hörbarkeit verstärkt wird.Die Schwingung einer Saite ohne Resonanzkörper könnte man kaum wahrnehmen. Deshalb wird die Schwingung auf den Geigenkorpus übertragen, der nun auch noch das in ihm enthaltene Luftvolumen zum Mitschwingen bringt. Material und Form des Geigenkorpus werden so gewählt, dass einerseits eine gute Verstärkung (Resonanz) bei möglichst vielen unterschiedlichen Frequenzen eintritt. Durch die Eigenfrequenzen der einzelnen Teile und die des Gesamtkörpers werden darüber hinaus bestimmte Grund- und Obertöne besonders verstärkt bzw. zusätzlich erzeugt. Es entsteht der individuelle Klangcharakter jeder einzelnen Geige. Hinweise und Ideen:Anhand eines praktischen Beispiels aus der Musik wird die Wichtigkeit von Physik und Akustik auch für Kunst und Kommunikation klar. Unterrichtsbezug:Schall/Akustik: KenngrößenSchwingungen und Wellen

Bild

Siemens Stiftung

Speech signal - individual word

Chart:
Screenshot of the oscillographic curve of the spoken word "dogs".

Speech sounds are fluctuating sound signals where the composition of frequencies changes all the time.
Aperiodical overlap periodical parts. Unlike noises, some of which have similar frequency curves, sound in speech is always the carrier of meaning or of messages sent out by the speaker. Other noises like smacking of lips, hissing, rhythms, basic pitch are typical of the individual (acoustic fingerprint) but not essential for the speech content!

Information and ideas:
Supplementary to worksheets and transparencies.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves
Communication and understanding

Bild

Siemens Stiftung

Speech recognition sentence - syllable - phoneme

Chart:
The components of speech, from phoneme to sentence presented visually.

The graphic shows the oscilloscope curve of the spoken sentence "It?s raining cats and dogs" and excerpts from the units from which speech is composed: sentence, word, phoneme.

Information and ideas:
Speech recognition and speech synthesis are very topical themes in the field of information and communication technology.
Further information on this graphic is available as information sheet on the media portal of the Siemens Stiftung.

Relevant for teaching:
The human body
Structure and function of a sense organ
Reception of impulses and information transmission
Sensory perception