Field-plotting kit (including sheets of carbon-loaded conducting paper, silver paint, connecting wires and sweeping pen) or PASCO Equipotential and Field Mapper; Variable dc power supply; Potential-divider (formed by connecting resistors on a breadboard); digital multimeter.
Theory: Equipotentials and Curvilinear Squares It is evident that along an equipotential lift in that respect can be no electric field (since E = - dV/dx). It follows that a flux line moldiness intersect an equipotential surface at right angles. Consider a small divisor of an electric field as shown in Fig. 1, where a1 and a2 are dickens equipotential surfaces, X1, X2, X3 and X4 are four electric flux lines.
x1 x2 dy d? a2 a1 V V + dV
Figure 1
X dx
x4 x3
dz d?
1
The get flux passing through a1 is:
d? ? D ? dA
where D is the electric flux density of area a1.
(1)
According to Gausss Law, the surface integral of the electric flux density must equal the total charge enclosed:
Q ? ? ? ? D ? dA
(2)
mental ability C ?
dQ D ? dzdy D ? dz ? dy dy dy ? ? ? ? 0? r dz ? ? ?dz ? dV dV E ? dx dx dx
(3)
where ?0 = 8.85 ? 10-12 F/m is the permittivity of free space and ?r is the relative permittivity of the dielectric. If we can draw equipotentials and flux lines such that they form curving squares (squares with curved sides (see Fig. 2), then dy and dx are equal and the capacitance of each curvilinear square (or cell) will be ?dz. In the system shown in Fig. 2, the dielectric may be considered to be made up of a large number of such cells in serial publication and...If you want to get a full essay, order it on our website: Orderessay
If you want to get a full essay, wisit our page: write my essay .
No comments:
Post a Comment