Introduction to the World of Physics. Методическое пособие по переводу научно-технических текстов. Лидия Страутман
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name="not_supported_in_fb2_underline">transformers, power storage devices, electric power transmission, (such as for propulsion of vactrains or ), magnetic levitation devices, and fault current limiters. However, superconductivity is sensitive to moving magnetic fields, so applications that use alternating current (such as transformers) will be more difficult to develop than those that rely upon direct current.
Superconductors in popular culture
Superconductivity is a popular device in science fiction, due to the simplicity of the underlying concept – zero electrical resistance – and the rich technological possibilities. One of the first mentions of the phenomenon occurred in 's novel Beyond This Horizon (1942). Notably, the use of a fictional room temperature superconductor was a major plot point in the Ringworld novels by Larry Niven, first published in 1970. Organic superconductors were featured in a science fiction novel by physicist Robert L. Forward. Also, superconducting magnets may be invoked to generate the powerful needed by Bussard ramjets, a type of spacecraft commonly encountered in science fiction.
The most troublesome property of real superconductors, the need for cryogenic cooling, is often circumvented by postulating the existence of room temperature superconductors. Many stories attribute additional properties to their fictional superconductors, ranging from infinite heat (thermal) conductivity in Niven's novels to providing power to an interstellar travel device in the Stargate movie and TV series (real superconductors conduct heat poorly, though superfluid has immense but finite heat conductivity).
Answer the questions.
1. What does the Large Electron-Positron Collider (LEP) mean?
2. What is the simplest method to measure the electrical resistance?
3. What are superconductors also able to maintain?
4. In what type is superconductivity abruptly lost when the strength of the applied field rises above a critical value?
5. Are superconductors used to make some of the most powerful electromagnets?
Put in a preposition where necessary.
1. Most ___ the physical properties ___ superconductors vary ___ material ___material, such as the heat capacity and the critical temperature ____ which superconductivity disappears. 2. Electric cables use ___ the European Organization ___ Nuclear Research (CERN). 3. Regular cables (background) ___ 12,500 amps ___ electric current used ___ a particle accelerator called the Large Electron-Positron Collider (LEP); superconductive cable (foreground) ___ the same amount ___ electric current used ___the Large Hadron Collider (LHC). 4. The energy supplied __ the fluid needs to be greater than the thermal energy (temperature) __the lattice in order for superconductivity __appear.
Complete the sentences with the relative clause: which, when.
1. An example of a common property of superconductors is that they all have exactly zero resistivity to low applied currents ___there is no magnetic field present. 2.Individual properties include the heat capacity and the critical temperature at ___ superconductivity is destroyed. 3.Most of the physical properties of superconductors vary from material to material, such as the heat capacity and the critical temperature above ___ superconductivity disappears. 4. If the voltage is zero, then the resistance is zero, ___means that the electric current is flowing freely through the sample and the sample is in its superconducting state. 5. In superconducting materials, the characteristics of superconductivity appear ___the temperature T is lowered below a critical temperature Tc.
Put in a/an or the where necessary.
1. ___simplest method to measure ___ electrical resistance of ___sample of some material is to place it in ___electrical circuit in series with ___current source "I" and measure the resulting voltage "U" across ___sample. 2. In __normal conductor, ___electrical current may be visualized as ___fluid of electrons moving across __heavy lattice (the conducting material), consisting of atoms that are electrically neutral. 3. When __ superconductor is placed in __ weak external , ___ field penetrates ___ superconductor for only __ short distance, called ___penetration depth. 4. This is called ___ Meissner effect, and is ___defining characteristic of superconductivity.
Put the verb into the correct form.
1. Experiments ___ that currents in superconducting coils can persist for years without any measurable degradation. (demonstrate) 2. Experimental evidence ___to a current lifetime of at least 100,000 years, and theoretical estimates for the lifetime of persistent current exceed the lifetime of the universe. (point) 3.Conventional superconductors usually___ critical temperatures ranging from less than 1 K to around 20 K. (have) 4. The Meissner effect ___down when the applied magnetic field is too large. (break) 5. ___ Meissner effect states that ____superconductor expels all magnetic fields.
Complete the sentence. Use the comparative or superlative form.
1. ____(simple) method to measure the electrical resistance of a sample of some material is to place it in an electrical circuit in series with a current source "I" and measure the resulting voltage "U" across the sample. 2. ___ (high) critical temperature found for a conventional superconductor is 39 K for magnesium diboride (MgB2). 3. ___ (troublesome) property of real superconductors, the need for cryogenic cooling, is often circumvented by postulating the existence of room temperature superconductors.4. Superconductors are used to build Josephson junctions, which are the building blocks of SQUIDs – ____ (sensitive) magnetometers known
Put questions to the underlined words
1. Individual properties include at which superconductivity is destroyed.
2. have exactly zero resistivity to low applied currents when there is no magnetic field present.
3. In superconducting materials, the characteristics of superconductivity appear when below a critical temperature Tc.
4. When a superconductor is placed in a weak external , the field penetrates the superconductor for only a short distance, after which it decays rapidly to zero.
5. At a second critical field strength, superconductivity
LESSON 5
Active vocabulary
Fullerene – фуллерен, бакибол (молекула углерода C2n в форме полого выпуклого многогранника)
Consist of – состоять из
Entirely – полностью
Resemble – напоминать
Allotrope-аллотропная модификация
Similar – похожий
Link – соединять
Derivative – преобразование
Carbon – углерод
Trap – схватывать
Planar