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Which of the two semiconductor material Si or Ge has larger conductivity at room temperature?
Wiki User
∙ 11y ago
Ge has higher conductivity than Si. Because at room temperature the electron and hole mobility for Ge is larger than those of Si. Another explanation is the lower band gap of Ge than Si.
Wiki User
∙ 11y ago
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What does a thyristor do in a circuit?
A thyristor is a solid state three terminal electronic power switch with two power terminals which carry the operational part of the device current and one gate or trigger terminal which is used to switch on the thyristor when required.Whenever the current flowing though it changes diirection or simply falls to zero, a thyristor will switch off.Unlike a transistor, after its gate/trigger signal is removed a thyristor will remain switched on for as long as the direction of the current flowing through it remains the same, even if the amperage of that current changes.Unlike a mechanical switch the thyristor has operational supply polarities ( positive & negative of the supply ) which have to be observed. Therefore it can switch on and conduct for one supply polarity only.Since it is a solid state device a thyristor can operate at much faster switching speeds than any electro-mechanical switch.With a DC supply of correct polarity, a thyristor will conduct when triggered but will not then switch off till the current is interrupted by some other means such as removal of the supply or by use other, much more complex, circuitry which forces the current to flow in the reverse direction.With an AC supply, when triggered a thyristor will conduct when the supply is of correct polarity and will then automatically switch off when the AC supply polarity reverses.For controlled operation in both directions, using the gate as a trigger on the both the forward and the reverse part of the AC Supply, a second thyristor connected with reverse polarity has to be used in parallel with the first one. This idea is basically what is used to make AC lamp dimmers nowadays.========================================================A thyristor is a transistor having a thyratron-like characteristic; as collector current is increased to a critical value, the alpha (amplification factor) of the unit rises above unity to give a high-speed triggering action.That description just given (now shown in italics) is wrong! It is not for a thyristor but for a thermistor!A thermistor is a device with 2 wires coming out of it which changes its resistance to electrical current flow as its temperature is changed. They are used in devices that have to perform some job based on the temperature of the medium they are in.The thyristor is a solid-state semiconductor device with four layers of alternating N- and P-type material. They act as bi-stable switches, conducting when their gate receives a current pulse, and continue to conduct for as long as they are forward biased. (That is, for as long as the voltage across the device has not reversed).Some sources define silicon controlled rectifiers and thyristors as synonymous. Other sources define thyristors as a larger set of devices with at least four layers of alternating N and P-type material.========================================================Re. the error shown in italics above... The first answer at the top of the page is correct: a thyristor (aka SCR or Silicon Controlled Rectifier) is a four layer solid-state switch, and a thermistor is a temperature-sensitive device consisting of a material with a high thermal coefficient of resistance, either positive or negative.Thyristors are solid-state semiconductor devices with four layers of alternating N- and P-type material. They act as bi-stable switches, conducting when their gate receives a current pulse, and continue to conduct for as long as they are forward-biased (That is, as long as the voltage across the device has not reversed).
Why the size of a fuse holder increase as the rating of a fuse?
As a general rule, the larger the current rating of the fuse, the larger will be the fuse holder (or at least the metal contacts) because it will have to be capable of handling larger currents without overheating.
The larger the conductor the Higher the resistanc Lower the ampacity Higher the voltage Lower the resistance?
No. The larger the conductor the lower the resistance and the higher the ampacity.
Can wire size make a difference to the amperage?
Yes, as the wire size physically becomes larger so doesits capacity to handle a larger current.
What technologies uses solar cells to produce electricity?
Basicaly in solar cells the photons are converted to electrons . The solar cells that you see on calculators and satellites are also called photovoltaic (PV) cells, which as the name implies (photo meaning "light" and voltaic meaning "electricity"), convert sunlight directly into electricity. A module is a group of cells connected electrically and packaged into a frame (more commonly known as a solar panel), which can then be grouped into larger solar arrays, like the one operating at Nellis Air Force Base in Nevada. Photovoltaic cells are made of special materials called semiconductors such as silicon, which is currently used most commonly. Basically, when light strikes the cell, a certain portion of it is absorbed within the semiconductor material. This means that the energy of the absorbed light is transferred to the semiconductor. The energy knocks electrons loose, allowing them to flow freely. PV cells also all have one or more electric field that acts to force electrons freed by light absorption to flow in a certain direction. This flow of electrons is a current, and by placing metal contacts on the top and bottom of the PV cell, we can draw that current off for external use, say, to power a calculator. This current, together with the cell's voltage (which is a result of its built-in electric field or fields), defines the power (or wattage) that the solar cell can produce. That's the basic process, but there's really much more to it. On the next page, let's take a deeper look into one example of a PV cell: the single-crystal silicon cell.
Why carbon is not used as semiconductor material?
carbon is not used as the semiconductor because it has larger band gap than silicon and germenium
What is higher 5.8e7 or 9.5e5 conductivity of metals?
5.8e7 is a larger number than 9.5e5. 5.8e7 can be written as 58,000,000, and 9.5e5 can be written as 950,000. Conductivity is a measure of the ability of a material to conduct electricity. A large conductivity means that the material conducts electricity well. The units of electrical conductivity are siemens per meter (Sm-1).
Why does density make it difficult for electricity to pass through?
Electricity takes the path of least resistance. Conductivity of a material has a larger impact than density does.
What is a large object at the same temperature as a smaller one has more or less thermal energy?
Thermal energy depends on mass, temperature and specific heat capacity of the material. Larger means, is that in mass? If so then thermal energy would be more in larger compared to that smaller at the same temperature provided both are made up of the same material.
What temperature is always larger kelvin or celsius?
It is the Kelvin temperature! :)
Which temperature is always larger -an objects Celsius temperatureor its kelvin temperature?
kelvin
conclusion and recommendation of lab heat transfer of first law termodynamics?
Conclusion The lab experiment on heat transfer of first law thermodynamics has demonstrated that heat energy can be transferred from one body to another through conduction, convection, and radiation. The data collected in this experiment shows that the rate of heat transfer is determined by the thermal conductivity of the material, the surface area of the material, and the temperature difference between the materials. The results of the experiment suggest that the higher the thermal conductivity of the material, the greater the rate of heat transfer. In addition, the higher the temperature difference between the two materials, the more heat will be transferred. Furthermore, the larger the surface area of the material, the greater the rate of heat transfer. Recommendation This lab experiment has shown that heat transfer is a complex process and can be further explored by performing more experiments with different materials and different temperature differences. In addition, this experiment has shown that the factors which affect heat transfer, such as thermal conductivity and surface area, can be manipulated to increase or decrease the rate of heat transfer. Therefore, it is recommended that further experiments should be conducted in order to further understand how these factors interact to affect the rate of heat transfer. Additionally, it is recommended that experiments should be conducted to explore how different materials and different temperature differences affect the rate of heat transfer. Finally, it is recommended that experiments should be conducted to explore how different materials and different surface areas affect the rate of heat transfer.
Why does rock material sink when convention takes place?
A material that has a larger density than the surrounding material has the natural tendency to sink.
Which temperature is always larger an objects's Celsius temperature or its kelvin temperature?
Kelvin. Kelvin (K) = oC + 273.15
Is celsius temperature larger then kelvin temperature?
No the Kelvin temperature is higher. The conversion for Kelvin to Celsius is K=c+273.15.
Which temperature is always larger-an objects celsius temperature or its kelvin temperature?
Kelvin is always higher - by some 273 degrees.
The magnitude of the resistance of a wire depends on?
Temperature, Length of wire, Area of the cross-section of wire and nature of the material.
