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The first semiconductors were discovered in passing when people wanted to make the light bulb more economical. Since then, a lot has changed about them. The film retraces this development and explains not only how the diode works, but also some important technical terms and the use of semiconductor diodes.
For a surface to reflect light, it must be very smooth. A regular reflection is given, for example, by processed glass and metal, which are used to make mirrors. The film explains the law of reflection, the creation of illusions through partial reflection, and that the mirror image is a result of our own perception.
Optical lenses are transparent, light-refracting bodies with at least one curved surface. The video introduces the different forms of lenses and how they work and shows their uses. Important terms such as focal point, refractive power and focal length are explained and the two lens formulas are derived.
If the curvature of a curved mirror is convex, it distorts the mirror image. If it is concave, this is also true, except that the image is also upside down. The film explains why this is so and how the laws of reflection explain it. In addition, the video shows possible applications for everyday life.
Levers are simple machines, or more precisely, they are mechanical force converters that magnify the force which is applied. The film explains the law of levers and shows the different forms of levers. Examples of different lever tools are given, such as scissors, tweezers, wheelbarrows, and nutcrackers.
The electrical resistance is defined as the quotient of the voltage and the strength of the current flowing in a circuit. At the same time, resistance also refers to a component with which a certain resistance can be realized in an electrical circuit. The film explains both terms using understandable examples.
Georg Simon Ohm discovered that voltage and current are interdependent. This video explains electrical resistance, Ohm´s law and the relationships that can be derived from it. The influence of length, strength, and temperature of a conductor as well as the calculation of electrical resistance are further topics.
The subject of this film is electromagnetic induction. A conductor loop suspended in a magnetic field illustrates how mechanical energy can be converted into electrical energy. A brief history of electromagnetic induction is given, the AC and DC voltages are explained and areas of application in industry are shown.
Electricity flowing through a wire generates a magnetic field. If this wire is twisted into a coil, the magnetic fields of the individual turns merge into a single stronger field. An iron core in the middle can intensify this effect. With this description, the video explains the construction of an electromagnet.
A electromagnet is made up of a coil with an iron core around which a magnetic field is generated as soon as electricity flows. This film shows how electromagnets can be used, for example as relays for high voltage circuits, for doorbells, in magnetic resonance therapy, and in particle accelerators.
The subject of this video is energy. There is the mechanical, the thermal and the electrical energy. Energy is not produced or consumed, but transformed. The film explains this using the law of conservation of energy. It is shown how one form of energy is converted into another, and the unit joule is explained.
Inertia is a physical property of all bodies. The video explains the law of inertia, according to which all bodies remain at rest or in uniform motion until an external action stops it. We encounter the law of inertia everywhere in everyday life, as the film illustrates with examples such as car and train travel.
Light travels at very high speed in a vacuum as well as in the air. As soon as it hits a denser material, however, its speed is slowed down. The film explains the refractive index, demonstrates why light rays are deflected in water, for example, and shows what angle is needed for a total reflection.
Power is a measure of the speed of work, and the watt is the unit in which energy consumption is measured. The film gives the definition of watt. You can compare mechanical, thermal and electrical power and easily convert them into each other. This video explains why and how this conversion is possible.
Lorentz force describes the effect of magnetic fields on moving electrons. It acts perpendicularly to the magnet´s field lines and to the direction of the electrons. The film shows how to determine the direction of movement of the electrons using the three-finger rule and where this force is used for technical purposes.
This video explains the concept of a magnetic field. It clearly describes some essential effects of magnetism and illustrates the concept of field lines. The film shows what the Earth´s magnetic field is all about, it clarifies geographical and magnetic poles and goes into the phenomenon of declination.
Mass is one of the seven basic physical quantities. This video gives an understandable definition of this quantity, names its unit of measurement and explains how it is related to the force of weight. Colloquially and outside the physical context, mass is also called weight, which can lead to confusion.
The moon does not shine itself, but only reflects the light of the sun. That is why the phases of the moon depend on it. The film shows how the moon changes in our perception depending on the angle it is at to the sun. At an angle of zero degrees it is new moon, at an angle of 180 degrees it is full moon.
Optical devices influence the course of light rays through lenses. The film shows how lenses are made in the eye and in visual aids such as glasses. The much stronger lenses of magnifying glasses and microscopes are also examined in detail. It is explained how exactly the multiple magnification is achieved.
For a temperature measurement procedure to be exact, it has to be reliable and repeatable. This films looks at different temperature measuring devices, namely the thermometer, the bimetallic thermometer, and the resistance thermometer, which depend on changeable substance properties at different temperatures.
Taking water as an example, the film explains the different states of aggregation of a substance. Below 0 °C, water is solid – it exists as ice. At its melting temperature of 0 °C it takes on liquid form, and at boiling temperature of 100 °C it changes to the gaseous state at normal pressure.
When light rays fall through a small hole in the front wall of an otherwise light-proof box, the image of the object that is in direct line in front of the hole is imaged overhead on the inside back of the box. The film describes step by step how this image is created and how to calculate the image size.
With the colours blue, yellow and purple, all colours can be produced. This is due to subtractive colour mixing: the colours act like a filter that prevents you from still seeing the original colours. The video explains understandable how the absorption spectrum of the filter makes some colours visible.
Eine unsichtbare Kraft zieht Metallgegenstände an. Was macht einige Gegenstände magnetisch und andere nicht? Der Film zeigt in anschaulichen Animationen den Aufbau von Magneten und befasst sich mit Theorie und praktischer Anwendung magnetischer Felder wie zum Beispiel in Festplatten und Mikrofonen.
This video shows how the state of motion, gravity and magnetic attraction of objects changes when different physical forces act on them. The film shows that the effects of these forces are measured in Newtons and that they are vector quantities. The law of interaction is also explained with examples.
Der alternde Werbefilmer Fernando entflieht dem Alltag in Madrid und besucht seinen Freund Miguel Angel auf Menorca. Er wohnt bei dessen Künstlerfreundin Nuria und verliebt sich in sie, doch sie muss plötzlich die Insel verlassen. Fernando freundet sich mit Miguels Tochter an, die auch Liebeskummer hat.
Eigentlich war die Zuckermühle das Letzte, was in Melaza noch lief, und nun ist sie auch geschlossen worden. Zu den wenigen Verbliebenen hier zählen Aldo und Monica, die sich fragen, wie es nun für sie weitergehen soll. Doch Kuba ist nicht umsonst die Insel des Einfallsreichtums und der Improvisation.
Im Süden Chiles haben Manenas Eltern in einer abgelegenen Gegend ein Ferienhaus. Hin und wieder kommt es hier noch zu Reibereien zwischen Ureinwohnern und weißen Landbesitzern. Manenas Eltern schotten sich ab, doch das Mädchen lernt Pedro kennen, einen Jungen der Mapuche, und freundet sich mit ihm an.
Paco de Lucia war der wohl berühmteste Flamencogitarrist weltweit. Sein Aufwachsen und sein Werdegang sind unzertrennlich mit der Entwicklung des Flamencos verknüpft. Dieser Film mischt historische Aufnahmen mit neuen aus dem Studio, von Konzerten und aus der privaten Umgebung, aufgenommen von Pacos Sohn.
Der junge Anwalt Luca verfällt in Buenos Aires der schönen Barbara gleich beim ersten Treffen. Er nimmt sie mit zu sich nach Hause, doch es folgt ein bitteres Erwachen, als Barbara mitsamt seiner Anzahlung für ein Haus am nächsten Morgen weg ist. Luca macht sich auf die Suche und findet Unglaubliches.