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The difference in the electron and hole mobilities is responsible for the small negative Hall coefficient of intrisic semiconductors.
Refs: C.M.Hurd : Hall effect in metals and alloys
R.Asokamani :solid state physics
Busch& Schade; Solid state Physics
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What is Halls process an American student hall discover it?
I do not know i am asking from you
What is the basic difference between relaxation oscillator and RC oscillator?
The difference between an RC and LC is that the frequency - determining device in the RC oscillator is not a tank circuit. LC can operate with A or C biasing, while RC can only operate with A.
Why 6 db is a good attenuation?
6 dB is not good nor bad as an attenuation, if the context and the signal that is attenuated is not specified. As a rule of thumb, addition between dBs is multiplication between linear attenuation, thus since 3dB is a division of the power by two, 6 dB means a division of the power by 4. Just to give an idea: In free space, without obstacles and reflections, the power of a normal voice attenuates 6 dB in dry air in about 230 cm (assuming 180° directional sound emission of the mouth, that is reasonable). This is the combined action of intrinsic air attenuation (the sound ordered power is converted by traversing air in disordered oscillations of molecules: i.e. heath) that is very small (about 1 dB/km) and of the increase of the area where the power is distributed, that going farer and farer from the source is a sphere of greater and greater radius so that power decrease due to this last effect as the square power of distance from source. The humidity further reduces air intrinsic attenuation, but since the dominant phenomenon is the other, we can say that practically nothing changes. If music is considered, the situation is more complex. Music frequencies are much more extended than voice frequencies and attenuation of the material depends on frequency (while attenuation due to distance does not, as it is intuitive). High frequencies attenuates in air much more than low frequencies, for example 50 kHz attenuates about 0.9 dB/m in dry air for 180° directional sound emission. Thus attenuation also imply a small distortion of music due to its dependence on frequency. However this effect is not so relevant to be problematic when hearing music in concert halls, due both to the small distance and to the logarithmic sensitivity characteristic of out ears. Moreover in concert halls there are a lot of reflections that are exploited in the design of a good concert hall to concentrate the sound on the public, thus the real attenuation is much reduced by the fact that power diverging from the source is redirected towards the hall center by reflections. A problem to avoid in such a design is to exploit reflections from objects too far from the source or the hall. In this case reflections recover energy, but are also delayed with respect to the original sound, creating a bad echo effect. Light exhibit similar behavior, but much more evident due to the huge frequency extension of visible light.
How is acoustics used in the design of concert halls?
Auditorium acoustics is a very specialized field at the intersection of acoustics and civil engineering.The two most important properties are Reverberation Control, and the control of Early Reflections.Wallace Clement Sabine was an US scientist acoustician who formulated much of the early foundation of acoustic measurements and of sound control in buildings.Before his time, the design of auditoria was very much a hit and miss situation. Some, such as the 'Big Music Hall' in Vienna was a very successful design, and was copied many times round the world. And much music was composed for this famous theatre. Other less successful attempts merely became warehouses.Chamber music is intended to be performed in small chambers (living rooms) of low reverberance, and the music for these will fail to be perfect in a larger space. Analogously, Cathedral music is intended to be heard in rooms with several seconds reverberation time, and indeed speech may be difficult, and has led to the style of speaking of a few words, followed by a pause to allow the echoes to decay.Sufficient. Leo Beranek is worth a look up, as is Harris, Cyril M.
What happens in a winding house of a mine?
The winding house houses the engine that raises and lowers the mine's cage (lift).
What has the author John H Halls written?
John H. Hall has written: 'Semiconductor design and implementation issues in integrated vehicle electronics' 'The word baptizo defined' -- subject(s): Accessible book, Baptism, Infant baptism
Where is the Halls Public Library in Halls located?
The address of the Halls Public Library is: 110 North Church Street, Halls, 38040 0236
What is the new halls flavor?
Halls Lime
Who is the guy in the elevator in the Halls commercial?
It is not known who the guy is in the elevator in the Halls commercial. The Halls commercial premiered in 2008.
What are the halls to be decked with?
what aren't the halls to be decked with is the real question
What are the halls to be decked?
what aren't the halls to be decked with is the real question
How do you get a wand on Halls of Hogwarts?
You don't get a wand on Halls of Hogwarts.
When was Halls of Illusions created?
Halls of Illusions was created in 1997.
When was Running the Halls created?
Running the Halls was created in 1993.
When was The Egyptian Halls created?
The Egyptian Halls was created in 1872.
When did Halls of the Things happen?
Halls of the Things happened in 1983.
When was The Halls of Ivy created?
The Halls of Ivy was created in 1954.
