Magnetic lield

If one looks along the strip in the direction of the current, with the magnetic lield directed downward, then, with si rips of antimony, cohall, zinc, or iron, the electric potential drop is toward the right and the effect is said to he positive. With gold, silver, platinum, nickel, bismuth, copper, and aluminum, it is toward the left, and Ihe effect is called negative. The transverse electric potential gradient per anil magnetic lield intensity per unit current density is called the Hall coefficient" for the metal in question Thus, the Hall coeflicienL is delined us... 

The Hilbert (Gb> is [he eleeiromagnelic CGS uni of nlaguclomotiv c force. The ampere lor unipeiv rum i tA is ihe SI unil. Tire tiersted (Oci is Ihe clccirninngneuc CGS unil of magnetic lield strength The ampere per merer (A/m) is the SI unit. 

To understand the absorption process, and in particular the measuremem of absorption, a classical picture of the behavior of a charged particle in a magnetic lield is helpful. 

Let us firsl consider the effect of the methylene protons in ethanol on the resonance of the molhyl protons. Recall that the ratio of protons in the two possible spin stales is very nearly unity, even in a strong magnetic lield. We then imagine that the two methylene protons in the molecule can have four possible combinations of spin slates and that in an entire sample the number of each of these combinations will be approximately etjual. If wc represent the spin orientation of each nucleus with a small arrow, the bmr states arc as follows ... 

Many proion NMR inslrumenls employ a magnet that prinide , a Held strength of 4.69 T. At what frequency would the hydrogen nucleus absorb In such a lield. ... 

High Lield Nuclear Magnetic Resonance Laboratory... 

Fig. 197. [(CHjljNHJCoClj 2 HjO single crystal. Temperature dependence of zero-lield magnetic susceptibility measured parallel to the b axis [73L12].

Light may be regarded as a periodically fluctuating electric lield associated with a periodic magnetic held. The electric and magnetic held vectors are in phase with... 

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