Units
In the standard SI system of units, D is measured in coulombs per square meter (C/m2). This choice of units (together with measuring the magnetizing field H in amperes per meter (A/m)) is designed to absorb the electric and magnetic constants in the Maxwell's equations expressed in terms of free charge and current, and results in very simple forms for Gauss's law and the Ampère-Maxwell equation:
Choice of units has differed in history, for example in the Gaussian CGS system of units the unit of charge is defined so that E and D are expressed in the same units.
Read more about this topic: Electric Displacement Field
Famous quotes containing the word units:
“Even in harmonious families there is this double life: the group life, which is the one we can observe in our neighbour’s household, and, underneath, another—secret and passionate and intense—which is the real life that stamps the faces and gives character to the voices of our friends. Always in his mind each member of these social units is escaping, running away, trying to break the net which circumstances and his own affections have woven about him.”
—Willa Cather (1873–1947)