Profile
Settings
Refer your friends
Sign out
Introduction
If there are two objects with different electrical charges then an electrostatic field exists between the two objects. An electrostatic field also forms around a single body/object which is electrically charged with respect to its surroundings. A body is negatively charged (-) when it has an excess of electrons related to its surroundings. A body is positively charged (+) when it has insufficient number of electrons with respect to its surroundings. Electrostatic field is formed by a static charge.
Electrostatics
Electrostatics is defined as the branch of physics which deals with the phenomena and properties of stationary or slow-moving electric charges. Electrostatic arises from the forces which is exert by the electric charges on each other and are defined by Coulomb’s law.
Electrostatic fields bear a certain resemblance to magnetic fields. Objects attract each other when their charges have opposite polarity (+/-) and Objects repel each other when their charges have the same polarity (+/+ or -/-). Electrostatic flux lines near two oppositely charged objects are similar to magnetic flux lines between and around a pair of opposite magnetic poles. The electrostatic and magnetic fields differ. Electrostatic fields are checked/blocked by metallic objects, while magnetic fields can penetrate most (but not all) metals. Electrostatic fields arise from a voltage gradient or potential difference and can exist when charge carriers such as electrons are stationary (hence the “static” is “electrostatic”). Magnetic fields are created by the movement of charge carriers, i.e. current flow.
Coulomb’s Law of Electrostatics
Coulomb’s law of electrostatics provides an equation for the electric force between the electric charges.
According to Coulomb’s law of electrostatics electrostatic force between two point charges separated by a distance is proportional to the product of the magnitude of charges and is inversely proportional to the square of the distance between these two charges.
The Coulomb’s law is given as
Here,
q = Test charge
Q = Source charge
F = force
r = distance between charges
Electric/electrostatic field is produced by the electric charge or can be produced by time-varying magnetic fields.
Electrostatic field formula
Electric field is the force per unit charge so electrostatic field formula is given as
Here,
= constant called absolute permittivity
E = electric field/electrostatic field
Gauss Law
According to the Gauss Law, the total electric flux outside the closed surface is equal to the charge enclosed by that surface divided by the permittivity (). The electric flux in an area is the product of electric field and the area of the surface perpendicular to the field.
Total flux associated with the surface is 1/ ε0 times the total charge enclosed by the closed surface.
Hence, it is given as
∮E.ds = (1/ε0)) x Q
Electric Field using Gauss Law
The electrostatic field/electric field can be determined by following these steps.
- Firstly we need to find the spatial symmetry (spherical, planar, cylindrical) of distributed charge.
- Then, we have to determine a gaussian symmetry which is similar to the symmetry of spatial arrangement.
- Determine integral along with the gaussian surface and then define flux.
- Determine the charge which is enclosed by the Gaussian surface.
- Determine the electric field of distributed charge.
Positive Charged Particle
In positively charged particles, the total number of positive ions is more than the total number of negative ions. That is the total numbers of protons available in a particle are more than the number of electrons available in that particle. To make neutral, it attracts the electrons unless the positively charged particles become stable.
Negative Charged Particle
In negatively charged particles, the total number of negative ions is more than the total number of positive ions, that is the total numbers of electrons available in a particle are more than the number of protons available in that particle. To make itself neutral, the negatively charged particles pair with the protons unless it becomes stable.
Neutral Particle
In neutral particles, the total number of negative ions are equal to the total number of positive ions. That is the total numbers of electrons available in a particle are equal to the number of protons available in that particle.
Conclusion
If there are two objects with different electrical charges, then an electrostatic field exists between the two objects. An electrostatic field also forms around a single body/object which is electrically charged with respect to its surroundings. A body is negatively charged (-) when it has an excess of electrons related to its surroundings. A body is positively charged (+) when it has insufficient number of electrons with respect to its surroundings. Electrostatic field is formed by a static charge.
Electric/electrostatic field is produced by the electric charge or can be produced by time-varying magnetic fields.
In neutral particles, the total number of protons are equal to the total number of electrons.
In positively charged particles, the total number of protons is more than the total number of electrons.
In negatively charged particles, the total number of electrons are more than the total number of protons.
According to Gauss Law Total flux associated with the surface is 1/ ε0 times the total charge enclosed by the closed surface.
