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Electrical engineers often use transformers. They can easily turn a low primary voltage into an unequally higher or lower secondary voltage. How this works in detail, for what purposes one needs this transformation in everyday life and what electromagnetic induction is exactly, is explained in the film.
Archimedes originally set out the law of the lever. The film shows how it has been developed since then and how it leads directly to the law of rotation. The law is explained and its practical uses demonstrated, for instance the wheel and axle which is used in ship´s rudders and many times in bicycles.
The physical term work is defined as the force exerted on a body in a certain way. In physics, a distinction is made between the work of lifting, acceleration, deformation, tension and friction, as the video explains with the help of examples from everyday life. The unit used to measure work is the joule.
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.
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.
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.
In addition to conductors and non-conductors, there are also so-called semiconductors with regard to electrical conductivity. Using the example of silicon, the film explains how a substance can change from a non-conductor to a conductor under certain conditions. It mentions the many possible uses of semiconductors.
The invention of the diode was soon followed by the development of another electrode - the triode. This was the first amplifier. These amplifiers were used extensively until the transistor almost completely replaced them. As the video shows, electron tubes are now only used in high-end guitar amplifiers.
No other component is used as frequently in electronic devices as the transistor. This video tells the story of the component: how it was invented, how it revolutionized and drove technology, how exactly it works and what uses have been found for it over time - especially since the beginning of the digital age.
This film presents four common semiconductors that we use frequently in everyday life. It explains the structure and functioning of the thyristor, the triac, the photo-semiconductor, and the LED and shows examples of where they are used - such as washing machines, elevators, light switches and headlights.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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 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.
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.
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.