Diagram of electrolytic capacitor:
Explanation: In an electrolytic capacitor, two sheets of aluminum foil, separated by a fine gauges soaked in an electrolyte rolled up and encased in an aluminum or ceramic or plastic tube. The aluminum oxide is dielectric. The electrolytic capacitors can be used only for DC and should be connected with correct polarity. The electrolytic capacitors have the advantages of small size and low cost. The range of capacitor is from around 1 µF to 200 µF and working voltage up to 400 volt DC. Their main field of applications is in electronic circuit and filters circuits.