Capacitor and Inductor

Capacitor

• Capacitance is a measure of a component's ability to store charge.
• A capacitor is a device specially designed to have a certain amount of capacitance.
• This ability to store charge means that capacitors can be dangerous. Some common electronic devices, such as televisions, contain large capacitors that can hold a deadly charge long after the device has been turned off and unplugged. Just as you should always assume that a firearm is loaded, you should always assume that a capacitor is charged.

The amount of charge (q) stored is directly proportional to the applied voltage (v).

q = Cv

C = known as the capacitance of the capacitor, 

measured in Farad.

Capacitors in Parallel 

Suppose you have two or more capacitors connected in parallel, as in the picture above. To find their total capacitance, simply add the individual capacitances:

CT = C1 + C2 +  ... + Cn

Capacitors in Series

Suppose you have two or more capacitors connected in series, as in the picture above. To find their total capacitance, use the reciprocal formula:

 CT = 1 ÷ (1÷C1 + 1÷C2 +  ... + 1÷Cn)

Inductor

• An inductor is a device designed to have a certain amount of inductance.
• Here's the schematic symbol for an inductor: Inductor symbol.    
• Most of the inductors in our labs look similar to this: Inductor photograph 
• Typical inductors found in electronic equipment are in the microhenry (μH) or millihenry (mH) range. Recall that micro- means 10-6 and milli- means 10-3.

Inductors in Series

Suppose you have two or more inductors connected in series, as in the picture above. The total inductance is equal to the sum of the individual inductances:

LT = L1 + L2 +  ... + Ln

Inductor in Parallel

Suppose you have two or more inductors connected in parallel, as in the picture above. To find the total inductance, use the reciprocal formula:

LT = 1 ÷ (1÷L1 + 1÷L2 +  ... + 1÷Ln)