The electric capacitance of the flat condenser depends on the area of facings, a gap between them and also a type of the dielectric located in this gap. In the SI system the capacity is expressed in farads, but in practice derivatives of unit from it are for this purpose used.
Instruction
1. If condenser facings identical are also located strictly one above another, calculate the area of any of them. In case they different or one of them is displaced concerning another, calculate the area of that area in which they block each other. Use at the same time the standard formulas for calculation of the area of geometrical figures: rectangle (S=ab), circle (S=π(R^2)), etc. Surely translate the received area of SI units - square meters. Transfer distance between facings to meters.
2. In statements of the problem both the absolute, and relative dielectric permeability of the material located between condenser facings can be specified. The first of these sizes is expressed in farads on meter (if it not so, transfer it to these units), the second is dimensionless. In the latter case it is about the coefficient specifying how much the absolute dielectric permeability of substance is more than the same characteristic of a vacuum. Transfer relative dielectric permeability to absolute, having increased by an electric constant (it and is dielectric permeability of a vacuum). It makes 8.854187817*10^ (-12) F/m.
3. Received during the previous calculation (or set initially) increase absolute dielectric permeability of the substance located between facings by the area of field of overlapping of plates then divide into distance between them. The condenser capacity expressed in farads will turn out.
4. If necessary transfer result of calculation to more convenient units: microfarads, picofarads or nanofarade. Remember that in millifarada it is not accepted to specify electric capacitance of any condensers, irrespective of their design, in the equipment. Choosing unit of measure, you seek to make so that before a comma there were as little as possible signs.