2. Capacitance symbol: C, unit: F (farad) Capacitance reactance unit: ω (ohm)

3. Impedance symbol: Z, unit: Ω (ohm)

4. admittance symbol: y, unit: s (Siemens)

Extended data:

1, capacitance correlation formula:

Definition:? ; However, the size of the capacitance is not determined by Q (charge amount) or U (voltage), that is, the formula for determining the capacitance is: C=εS/4πkd.

Where ε is a constant, S is the relative area of the capacitor plates, D is the distance of the capacitor plates, and K is the electrostatic force constant. The capacitance of a common parallel plate capacitor is C=εS/d(ε is the dielectric constant of the medium between plates, S is the area of plates, and D is the distance between plates).

The formula for calculating the potential energy of capacitor is: E = Cu 2/2 = Qu/2 = Q 2/2c.

Multi-capacitor parallel calculation formula: C=C 1+C2+C3+…+Cn.

Calculation formula of multiple capacitors in series:1/c =1/c1+1/C2+…+1/cn.

Three capacitors are connected in series: c = (c1* C2 * C3)/(c1* C2+C2 * C3+c1* C3)

Second, the impedance formula

z = R+I(ωL– 1/(ωC))

Description: The load is a complex of three types: resistance, inductance and capacitance, which are collectively called "impedance" after being combined. The mathematical formula is: impedance z = r+I (ω l–1/(ω c)). Where r is resistance, ωL is inductive reactance, and 1/(ωC) is capacitive reactance.

( 1)If(ωl– 1/ωc)>； 0, called "inductive load";

(2) On the contrary, if (ω l–1/ω c)