The difference between inductance, capacitance, resistance, voltage, current, and power

Encyclopedia
09/21/2024

Distinction


  • Resistance: impedes current and dissipates energy.



  • Inductance: Stores magnetic field energy and opposes current changes.



  • Capacitors: Store electric field energy and oppose voltage changes.



  • Voltage: The force that drives the flow of electricity.



  • Current: The flow of charge, indicating the rate at which charge flows.


  • Power: The work done per unit time, indicating the rate of energy conversion.


Resistance definition


Resistance is a physical quantity in a circuit that impedes the flow of current. Resistive elements (such as resistors) can convert electrical energy into heat.


Peculiarity


  • Obstruction current: The resistance prevents the current from passing through, and the larger the value, the stronger the obstruction effect.



  • Energy dissipating components: Resistors are energy dissipating components, and the current passing through the resistors generates heat.



  • Ohm's Law: The relationship between voltage V, current I, and resistance R follows Ohm's law V=IR.


Apply


  • Current limiting: Used to limit current and protect other components in the circuit.



  • Voltage division: Used to build voltage division circuits.



  • Filter: Used in conjunction with capacitors to build RC filters.


Inductance definition


Inductance refers to the ability to store magnetic field energy in a circuit. An inductor (such as an inductor or coil) creates a counterelectromotive force when the current changes, which prevents the current from changing.


Peculiarity


  • Storage of magnetic field energy: inductors store magnetic field energy, the greater the value, the stronger the storage capacity.




  •  Anti-current change: The inductor opposes the change of current, that is, the reverse electromotive force is generated when the current increases, and the energy is released when the current decreases.



  • Inductive reactance: In AC circuits, inductors produce inductive reactance XL=2πfL, where f is the frequency.


Apply


  • Filter: Used to build LC filters to filter out high-frequency components in AC signals.



  • Energy storage: Used in switching power supplies to store energy and smooth current.



  • Choke coil: Used to prevent high-frequency signals from passing through, while allowing DC signals to pass through.


Capacitance (Capacitance, C)definition


Capacitance is the ability to store electric field energy in a circuit. Capacitive elements (such as capacitors) charge or discharge when the voltage changes, storing or releasing electric field energy.


Peculiarity


  • Storage of electric field energy: Capacitors store electric field energy, and the larger the value, the stronger the storage capacity.



  • Anti-voltage change: The capacitor opposes the change of voltage, that is, charges when the voltage rises and discharges when the voltage decreases.



  • Capacitive reactance: In an AC circuit, a capacitor produces a capacitive reactance XC= 1/2πfC, where f is the frequency.


Apply


  • Filter: Used to build RC filters to filter out low-frequency components in AC signals.



  • Coupling: Used to isolate direct coupling and transmit AC signals.




  • Energy storage: Used for energy storage, such as storing energy in a camera flash.


Voltage (Voltage, V)definition


Voltage refers to the potential difference between two points in a circuit, indicating the direction and intensity of charge movement. Voltage is what drives the flow of electricity.


Peculiarity


  • Potential difference: Voltage is the electric potential difference, which is measured in volts (V).



  • Driving current: Voltage is the cause of current flow.



  • Power supply: Power supply (e.g. battery, generator) provides voltage.


Apply


  • Power supply: Provides electrical energy in the circuit.



  • Measurement: Used to measure the potential difference in a circuit.


Current (Current, I)definition


Current refers to the flow of charge, representing the amount of charge passing through a cross section of a conductor in unit time.


Peculiarity


  • Charge flow: Current is formed by the flow of charges and is measured in amperes (A).



  • Direction: The direction of the current is specified as the direction of the positive charge flow.



  • Strength: The strength of the current indicates the rate at which charge flows.


Apply


  • Load: Drive load (such as light bulb, motor) work.



  • Measurement: Used to measure charge flow in a circuit.


Power (P)definition


Power refers to the work done per unit time, indicating the rate of energy conversion.


Peculiarity


  • Energy conversion: Power represents the rate of energy conversion, and its unit is watt (W).



  • Electric power: Electric power is determined by voltage V and current I, calculated by P=VI.


Apply


  • Energy consumption: Used to calculate the energy consumption in the circuit.

  • Efficiency: Used to evaluate the efficiency of a circuit or device.


Encyclopedia

The Electricity Encyclopedia is dedicated to accelerating the dissemination and application of electricity knowledge and adding impetus to the development and innovation of the electricity industry.

What is Biot Savart Law?
What is Biot Savart Law?
The Biot-Savart Law is employed to determine the magnetic field intensity dHnear a current-carrying conductor. In other words, it describes the relationship between the magnetic field intensity generated by a source current element. This law was formulated in 1820 by Jean-Baptiste Biot and Félix Savart. For a straight wire, the direction of the magnetic field adheres to the right-hand rule. The Biot-Savart Law is also referred to as Laplace’s law or Ampère’s law.Conside
Edwiin
05/20/2025
What is Peak Inverse Voltage (PIV)?
What is Peak Inverse Voltage (PIV)?
DefinitionThe maximum value of the reverse voltage that a PN junction or diode can withstand without damage is termed thePeak Inverse Voltage (PIV). This PIV rating is specified and explained in the datasheet provided by the manufacturer.However, if the voltage across the junction under reverse bias exceeds this specified value, the junction will be damaged.As shown in the figure above, a PN junction or diode is commonly used as a rectifier, i.e., to convert alternating current (AC) to direct cu
Edwiin
05/19/2025
What is Magnetoresistor?
What is Magnetoresistor?
Definition: When the resistance of certain metals and semiconductor materials changes in the presence of a magnetic field, this phenomenon is referred to as the magnetoresistance effect. The components that exhibit this effect are called magnetoresistors. Put simply, a magnetoresistor is a type of resistor whose resistance value fluctuates with the strength and direction of an external magnetic field.Magnetoresistors play a crucial role in detecting the presence of a magnetic field, measuring it
Encyclopedia
05/10/2025
How does the input voltage affect the current flowing through the load resistor in an ideal transformer?
How does the input voltage affect the current flowing through the load resistor in an ideal transformer?
How Input Voltage Affects the Current Through a Load Resistor in an Ideal TransformerAn ideal transformer is one that assumes no energy losses (such as copper loss or iron loss). Its primary function is to change the levels of voltage and current while ensuring that the input power equals the output power. The operation of an ideal transformer is based on the principle of electromagnetic induction, and there is a fixed turns ratio n between the primary and secondary coils, given by n=N2 /N1, whe
Encyclopedia
01/24/2025
Inquiry
Download
Experts Electrical is dedicated to serving the personnel in the global power industry.
Join Experts Electrical, not only can you discover power equipment and power knowledge, but also canhnd like - minded friends!