hall coefficient การใช้

The Hall coefficient is defined as the ratio of the induced electric field to the product of the current density and the applied magnetic field.
I've been trying to find electron and hole concentration data for carbon to calculate the Hall coefficient to predict the Hall p . d . across a thin carbon sheet.
A common source of confusion with the Hall Effect is that holes moving to the left are really electrons moving to the right, so one expects the same sign of the Hall coefficient for both electrons and holes.
Although the Drude model was fairly successful in describing the electron motion within metals, it has some erroneous aspects : it predicts the Hall coefficient with a wrong sign compared to experimental measurements, the assumed additional electronic heat capacity to the lattice heat capacity, namely \ frac { 3 } { 2 } k _ { B } per electron at elevated temperatures, is also inconsistent with experimental values since metals showed upon measurements no deviation from the Dulong-Petit law.