Electrostatic vs Electromagnetic
Static and dynamic electric fields are very important in the study of the electromagnetic field theory. A magnetic field is caused by a time varying electric field. Electrostatics and electromagnetism are two very important topics discussed in electromagnetic field theory. The applications of electromagnetism and electrostatics are enormous. It is vital to have a proper understanding in the concepts of electrostatics and electromagnetism in order to understand the fields such as electricity, magnetism, power generation, radio and other electromagnetic waves and many more. In this article, we are going to discuss what electrostatic and electromagnetic are, definitions of electrostatic and electromagnetic, their similarities, and finally the difference between electrostatic and electromagnetic.
The term “electro” means the electricity or any charge. Static means not varying with time. The field of electrostatics tackles the problems involving a static electric field. There are few main concepts in electrostatics. The mutual force acting on two charges of Q1 and Q2 placed distance r apart from each other in a medium having a permittivity of ε, is F = Q1 * Q2 /4πεr2. If both of the charges are of the same sign, the force is repellent. If the charges are of different signs, the force is attractive. Another important concept is the potential of the electric field. This is defined as the amount of work required to bring a test charge of 1C from infinity to the given point. The potential due to a point charge is equal to Q / 4πεr. For a potential energy of a charge Q1, the equation we get is Q * Q1 /4πεr2. A static electric field does not create a magnetic field.
Electromagnetism is one of the four basic forces in nature. Other three are weak force, strong force and gravity. The term electromagnetic can be broken into two words. Electro means anything that is associated with a charge. Magnetic means anything that is associated with magnets. The theory of electromagnetic (or more commonly known as the electromagnetic field theory) describes the relationship between electricity and magnetism. A time varying electric field causes a time varying magnetic field. A time varying magnetic field creates a time varying electric field. These concepts are used to generate electromagnetic waves. In electromagnetism, effects from both the electric field and the magnetic field are considered. The magnetic field created by the changing electric field is always perpendicular to the electric field and is proportional to the changing rate of the electric field and vice versa. James Clark Maxwell was the pioneer in postulating the electromagnetic theory. The electric theory and magnetic theory was developed separately by other scientists and Maxwell unified them.
What is the difference between Electromagnetic and Electrostatic?
• Electrostatic always refers to a time invariant electric field. This means a magnetic field is not present in electrostatics. Electromagnetic always refers to a time varying electric and magnetic fields.
• In the case of electromagnetism, separate static electric fields can occur. Electrostatics is a special case of electromagnetics.