What is Poynting Vector?
Poynting vector was introduced in 1884 by English physicist John Henry Poynting, thereby naming it after his name . Poynting vector is a tool used for studying energy flow in electromagnetic waves. In layman’s language, it is used to tell how much energy is being carried by an electromagnetic wave in a unit area. The formal definition is given below
Poynting vector represents the power per unit area transported by an electromagnetic wave. It is denoted by letter S.
Thereby this vector helps us understand how the transfer of energy works, and how can we determine the direction where energy is going to flow. For example, it helps us understand how waves being emitted from an antenna carry energy.
Poynting Vector
Poynting Vector as the name suggests is a quantity that has both magnitude and direction. In the electrical industry, whilst dealing with electromagnetic waves, we often have to come across some tools that can help us analyze these waves. If we think about how electromagnetic waves travel, we realize that we need a term to define the energy flux density of these waves and this is represented by Poynting Vector. Basically, the Poynting vector represents power per unit area. It generally is defined as the cross-product of an electric field and magnetic field, giving us the direction of energy flux which is in the direction of wave propagation. In this article, we will learn about Poynting Vector, its meaning, and its physical Interpretation. We will also discuss the components used in the formula of the Poynting vector. Later we will discuss some advantages and disadvantages of the Poynting vector and how are they put into use. We will conclude the article with some Frequently Asked Questions.
Table of Content
- What is Poynting Vector?
- Physical Interpretation of Poynting Vector
- Formula of Poynting
- Advantages of Poynting Vector
- Disadvantages of Poynting Vector
- Vector Applications of Poynting Vector
- Solved Examples