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In physics and chemistry, the Nernst Effect (also termed first Nernst–Ettingshausen effect, after Walther Nernst and Albert von Ettingshausen) is a thermoelectric (or thermomagnetic) phenomenon observed when a sample allowing electrical conduction is subjected to a magnetic field and a temperature gradient normal (perpendicular) to each other. An electric field will be induced normal to both. This effect is quantified by the Nernst coefficient |''N''|, which is defined to be :: where is the ''y''-component of the electric field that results from the magnetic field's ''z''-component and the temperature gradient . The reverse process is known as the Ettingshausen effect and also as the second Nernst-Ettingshausen effect. == Physical picture == Mobile energy carriers (for example conduction-band electrons in a semiconductor) will move along temperature gradients due to statistics and the relationship between temperature and kinetic energy. If there is a magnetic field transversal to the temperature gradient and the carriers are electrically charged, they experience a force perpendicular to their direction of motion (also the direction of the temperature gradient) and to the magnetic field. Thus, a perpendicular electric field is induced. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nernst effect」の詳細全文を読む スポンサード リンク
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