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Thermal radiation
1. Thermal radiation is electromagnetic radiation generated by the thermal motion of charged particles in matter. All matter with a temperature greater than absolute zero emits thermal radiation. The mechanism is that bodies with a temperature above absolute zero have atoms or molecules with kinetic energies which are changing, and these changes result in charge-acceleration and/or dipole oscillation of the charges that compose the atoms. This motion of charges produces electromagnetic radiation in the usual way. However, the side spectrum of this radiation reflects the wide spectrum of energies and accelerations of the charges in any piece of matter at even a single temperature.
2. Examples of thermal radiation include the visible light and infrared light emitted by an incandescent light bulb, the infrared radiation emitted by animals and detectable with an infrared camera, and the cosmic microwave background radiation. Thermal radiation is different from thermal convection and thermal conduction – a person near a raging bonfire feels radiant heating from the fire, even if the surrounding air is very cold.
3. Sunlight is thermal radiation generated by the hot plasma of the Sun. The Earth also emits thermal radiation, but at a much lower intensity and different spectral distribution (infrared rather than visible) because it is cooler. The Earth’s absorption of solar radiation, followed by its outgoing thermal radiation are the two most important processes that determine the temperature and climate of the Earth.

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What does solar light absorption by the Earth result in?

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Clerk: «_________________».
Customer: «I’d like to book two roundtrip tickets to Boston».

Gamma rays are the most powerful and are a ________ form of energy with no mass and no charge.

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Nanotechnology
1. Nanotechnology is the study of the controlling of matter on an atomic and molecular scale. Generally nanotechnology deals with structures of the size 100 nanometers or smaller in at least one dimension, and involves developing materials or devices within that size. Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.
2. Molecular nanotechnology describes engineered nanosystems operating on the molecular scale. Molecular nanotechnology is especially associated with the molecular assembler, a machine that can produce a desired structure or device atom-by-atom using the principles of mechanosynthesis.  
3. In general it is very difficult to assemble devices on the atomic scale, as all one has to position atoms are other atoms of comparable size and stickiness. Another view, put forth by Carlo Montemagno, is that future nanosystems will be hybrids of silicon technology and biological molecular machines. Yet another view, put forward by the late Richard Smalley, is that mechanosynthesis is impossible due to the difficulties in mechanically manipulating individual molecules.
4. There has been much debate on the future implications of nanotechnology. Nanotechnology has the potential to create many new materials and devices with a vast range of applications, such as in medicine, electronics and energy production.
On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios.
(Encyclopedia Wikipedia)

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Receptionist: «Can I help you?»
Customer: «________________»

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Teacher: «Give me that book. Will you?»
Student: «_______________».

You ________ do it today. You can do it tomorrow morning.

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A heat engine
1. In thermodynamics, a heat engine is a system that performs the conversion of heat or thermal energy to mechanical work. It does this by bringing a working substance from a high temperature state to a lower temperature state. A heat «source» generates thermal energy that brings the working substance in the high temperature state. The working substance generates work in the «working body» of the engine while transferring heat to the colder «sink» until it reaches a low temperature state. During this process some of the thermal energy is converted into work by exploiting the properties of the working substance. The working substance can be any system with a non-zero heat capacity, but it usually is a gas or liquid.
2. In general an engine converts energy to mechanical work. Heat engines distinguish themselves from other types of engines by the fact that their efficiency is fundamentally limited by Carnot’s theorem. Although this efficiency limitation can be a drawback, an advantage of heat engines is that most forms of energy can be easily converted to heat by processes like exothermic reactions (such as combustion), absorption of light or energetic particles, friction, dissipation and resistance. Since the heat source that supplies thermal energy to the engine can thus be powered by virtually any kind of energy, heat engines are very versatile and have a wide range of applicability.
3. Heat engines are often confused with the cycles they attempt to mimic. Typically when describing the physical device the term «engine» is used. When describing the model the term «cycle» is used.

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What constant property should the working substance possess in a heat engine?

He is known __________ much attention to his work.

Please wait in the waiting room, _______ the doctor is ready to see you.

The geographical centre of London is …

London was founded in _______ century BC by Julius Caesar.

The wide ________ displayed on your stand at the Fair impressed us very much.

A mechanic will carry ________ a full inspection of the car to see what caused the problem.

According to Faraday’s law of induction to produce an electromotive force a magnetic field _______ an electric circuit.

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Nuclear physics
1. The study of the nucleus of an atom is known as nuclear physics. As a result of this study, scientists have discovered ways of splitting the nucleus to release huge amounts of energy. There are two types of nuclear reactions: nuclear fission and nuclear fusion. A controlled nuclear reaction inside a power station can be used to provide heat and light for our homes.
2. Nuclear power stations use fission to produce their energy. Fast-moving atomic particles called neutrons are fired at the nucleus of an atom to split it. This splitting is called fission and it causes other atoms to split in a chain reaction. Some mass (the number of heavy particles inside an atom) is lost in the process. This is converted into large amounts of nuclear energy.
3. Nuclear fusion is a type of nuclear reaction that creates huge amounts of energy. It takes place naturally inside the sun, creating the heat energy that we need to survive on Earth. At temperatures of about 14 million C dgr. the nuclei of two hydrogen atoms fuse, or join together. In the process, some mass (the number of heavy particles inside an atom) is lost and converted into energy. Scientists are trying to develop this form of nuclear reaction as a safer alternative to the nuclear fission that takes place in power stations.

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