Cylindrical Capacitor

Definition

A cylindrical capacitor is a type of capacitor that consists of two concentric cylindrical conductors separated by an insulating material. It is used to store electrical charge and is commonly found in various electronic devices and circuits.

5 Must Know Facts For Your Next Test

1. The capacitance of a cylindrical capacitor is directly proportional to the length of the cylinders and inversely proportional to the natural logarithm of the ratio of the outer and inner radii.
2. Cylindrical capacitors are commonly used in high-frequency applications, such as in radio frequency (RF) circuits and transmission lines, due to their compact design and ability to handle high voltages.
3. The electric field in a cylindrical capacitor is radial, meaning it is directed outward from the inner conductor to the outer conductor.
4. Cylindrical capacitors can be used to create a voltage divider, which is a circuit that divides an input voltage into a smaller output voltage.
5. The energy stored in a cylindrical capacitor is proportional to the square of the applied voltage and the capacitance of the device.

Review Questions

• Explain the relationship between the capacitance of a cylindrical capacitor and its physical dimensions.
  • The capacitance of a cylindrical capacitor is directly proportional to the length of the cylinders and inversely proportional to the natural logarithm of the ratio of the outer and inner radii. This means that as the length of the cylinders increases, the capacitance also increases, and as the ratio of the outer and inner radii increases, the capacitance decreases. This relationship allows for the design of cylindrical capacitors with specific capacitance values based on the desired physical dimensions.
• Describe the electric field distribution within a cylindrical capacitor and how it differs from a parallel plate capacitor.
  • In a cylindrical capacitor, the electric field is radial, meaning it is directed outward from the inner conductor to the outer conductor. This is in contrast to a parallel plate capacitor, where the electric field is uniform and directed perpendicular to the plates. The radial nature of the electric field in a cylindrical capacitor allows for a more compact design and the ability to handle higher voltages, making it suitable for various high-frequency applications.
• Analyze how a cylindrical capacitor can be used to create a voltage divider circuit and discuss the factors that determine the output voltage.
  • A cylindrical capacitor can be used to create a voltage divider circuit, where the input voltage is divided between the capacitor and another resistive or capacitive component. The output voltage in this circuit is determined by the ratio of the capacitances or impedances of the components. In the case of a cylindrical capacitor, the output voltage will depend on the capacitance of the device, which is influenced by its physical dimensions, such as the length of the cylinders and the ratio of the outer and inner radii. By carefully selecting the dimensions of the cylindrical capacitor, the desired output voltage can be achieved, allowing for the creation of voltage divider circuits with specific voltage ratios.

Related terms

Parallel Plate Capacitor: A parallel plate capacitor is a type of capacitor that consists of two parallel conductive plates separated by an insulating material.

Dielectric Material: A dielectric material is an insulating material that can be polarized by an external electric field, allowing it to store electrical energy.

Electric Field:

An electric field is a region of space where an electric charge experiences a force, and it is typically represented by lines of force.