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The magnetic field is described in terms of poles, with either end of a magnet being referred to as a north or south pole. Learn about the similarities of electromagnets, permanent magnets or magnetized steel with help from a science teacher in this free video on physical science.
A DC circuit refers to a direct current circuit, which is a current that moves in one direction, as opposed to an alternating current. Find out how a cell or battery provides power to a DC circuit with help from a science teacher in this free video on physical science.
A wind energy system is a renewable energy system that turns wind energy into rotational energy and mechanical energy. Find out how windmills can power a generator with help from a science teacher in this free video on physical science.
A photon is a little packet of energy, an elementary particle that is the basic unit of light and electromagnetic radiation. Find out how people came to understand photons with help from a science teacher in this free video on physical science.
Hazardous waste can be broken down into waste that is chemically hazardous, physically hazardous or biologically hazardous. Find out how hazardous waste can be minimized or prevented with help from a science teacher in this free video on physical science.
An atom is very small and dense and consists of a nucleus and orbiting electrons. Discover how a collapsed atom can cause a black hole with help from a science teacher in this free video on physical science.
The carbon cycle involves trees absorbing carbon dioxide and emitting oxygen to keep the atmosphere balanced. Learn about the recent increase of carbon dioxide in the atmosphere with help from a science teacher in this free video on life science.
Convergence, in relation to physics, is the physical joining together of light. Discover how to identify convergence with a curved mirror with help from a science teacher in this free video on life science.
Natural selection refers to the idea that living creatures survive due to their ability to adapt to their environments. Find out why natural selection causes some species to die out over time with help from a science teacher in this free video on life science.
Polarized light is confined to one direction, and reflected light is polarized to some degree. Discover how polarized sunglasses work with help from a science teacher in this free video on physical science.
The instrument used to measure temperature is usually the thermometer, although a thermistor can also be used. Learn about the way in which a thermometer works on the basis of liquid expansion with help from a science teacher in this free video on physical science.
Transducers are used to convert incoming energy into some kind of an electrical signal. Learn about current examples of transducers, such as photo diodes, with help from a science teacher in this free video on physical science.
A half-wave rectifier has a diode in it, and this diode will remove half of the signal from an alternating current. Find out how a full-wave rectifier works, in addition to a half-wave rectifier, with help from a science teacher in this free video on physical science.
Static electricity results from electrons being knocked off of the surface of atoms, which leaves a net positive charge. Learn about conductors and insulators in static electricity with help from a science teacher in this free video on physical science.
Radon is one of a group of gases called inert gases, and it is naturally radioactive. Learn more about radon, the heaviest of the inert gases, with help from a science teacher in this free video on physical science.
Soft water is not physically soft, but soft water refers to the soluble mineral content of the water. Learn about soft water, which doesn't contain minerals that have been dissolved out of a rock structure, with help from a science teacher in this free video on physical science.
Hydrogen is a colorless gas that is lighter than air and very flammable. Learn more about hydrogen, the lightest of the elements, with help from a science teacher in this free video on physical science.
Magnetic domains don't exist in every substance, but they exist in ferromagnetics in material that is divided into lumps. Discover how magnetic domains relate to thermal energy with help from a science teacher in this free video on physical science.
A direct current is measured with a coil and field magnets, but alternating currents need to be measured with an oscilloscope. Learn about moving coil galvanometers with help from a science teacher in this free video on physical science.
Coherent light refers to light waves that are in phase with one another; waves that have the same amplitude. Learn about the monochromatic nature of coherent light with help from a science teacher in this free video on physical science.
Interference of light can arise in the form of constructive interference or destructive interference. Find out why interference of light isn't normally visible with help from a science teacher in this free video on physical science.
Polarization of light occurs when electromagnetic waves exist in more than one dimension, and a polarizing light vibrates in one direction. Learn about the role of crystals in the polarization of light with help from a science teacher in this free video on physical science.
Light dispersion is the way white light is split up into different colors when entering a different medium. Find out how a prism can show the splitting of white light into a rainbow with help from a science teacher in this free video on physical science.
Mercury, the planet, has a solid core containing iron, a magnetic field and silicone. Find out why Mercury has no atmosphere with help from a science teacher in this free video on physical science.
Uranium is found naturally in three different forms, all of which are radioactive. Find out about enriched uranium, which has a higher percentage of uranium 235 than natural uranium, with help from a science teacher in this free video on physical science.
Physical science is an encompassing term for the branches of natural science and science that study non-living systems, in contrast to the biological sciences. The foundations of the physical sciences rests upon key concepts and theories, each of which explains and/or models a particular aspect of the behavior of nature. Physical science can be divided into astronomy, chemistry, earth science and physics. In this free video series, a science teacher provides answers to a number of common questions regarding physical and life sciences. Learn about DC circuits, photons, wind energy systems and carbon cycles. Find out about natural selection, polarized light, static electricity, magnetic domains and nuclear energy. Get answers to a wide range of scientific questions in these free videos.
Steve Jones Steve Jones is an experienced mathematics and science teacher. He also has many years experience in the field of public speaking and debate, and he is an organizer of debate competitions for high school students. He is the chairman of the Hungarian branch of the English-Speaking Union, which is an international educational charity founded in 1918 to promote international understanding and friendship through the use of the English language.dkdk
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