Читать книгу Essentials of MRI Safety - Donald W. McRobbie - Страница 53

Gauss’s Law (Maxwell’s first equation) describes how electrical charges produce static electric fields E. Electric fields start at a positive charge and are directed towards their conclusion at negative charges (Figure 2.1). We are not going to use Gauss’s Law much, although it has relevance in minimizing unwanted electric fields in coil design, and at some tissue boundaries where charge may accumulate.

Figure 2.1 Electric field lines begin at a source of positive charge and terminate at a negative charge: (a) single point positive charge; (b) positive and negative point charges; (c) capacitor with a potential difference V between the plates.