Which of the following capacitors is marked for polarity ?

Air
Paper
Mica
Electrolytic

The correct answer is: D. Electrolytic

Explanation:

  • Air capacitors are non-polar, meaning they do not have a positive or negative terminal.
  • Paper capacitors are non-polar, meaning they do not have a positive or negative terminal.
  • Mica capacitors are non-polar, meaning they do not have a positive or negative terminal.
  • Electrolytic capacitors are polar, meaning they have a positive and negative terminal. The polarity of an electrolytic capacitor must be observed when connecting it to a circuit, otherwise the capacitor may be damaged.

Air capacitors are the simplest type of capacitor and are made up of two metal plates separated by a layer of air. They are non-polar and have a low capacitance.

Paper capacitors are made up of two metal plates separated by a layer of paper. They are non-polar and have a higher capacitance than air capacitors.

Mica capacitors are made up of two metal plates separated by a layer of mica. They are non-polar and have a higher capacitance than paper capacitors.

Electrolytic capacitors are made up of a metal anode, an oxide dielectric, and a metal cathode. The anode is the positive terminal and the cathode is the negative terminal. Electrolytic capacitors have a high capacitance but are polarized and must be connected to a circuit with the correct polarity.