Static Electric Field | Electrostatic Induction
Static Electric Field
We know there are two types of charge present in the nature (i) positive and (ii) negative charge. In positive charge, there is mainly deficiency of electrons and in negative charge there are excess of electrons. Now, we can simply understand the concepts of charge from a very basic example. Take a dry comb, comb your hair (which should be dry) two to three times, now take that comb near tiny pieces of paper, you will see that the paper pieces are getting attracted to the comb. This is the very basic example of electric charge and static electric field
. Due to friction there is movement of electrons between comb and hair, so one of them gets positively charged and another one gets negatively charged and as the paper is neutral (i.e. not charged) they get attracted to the comb.
So, we can see that there is an attraction force works between charged particle and neutral particle, it has been seen further that there is repulsion between two same charged particles and attraction between two oppositely charged particles. This happens due to the field created around a particle. This can be understood if we imagine a glowing bulb, the bulb can be taken as the charge and the visible light can be compared to static electric field, the characteristic of field is similar to the light in the sense that the intensity of the field is greater near the source and it fades as we move further from the source. Now from another point of view we can say that static electric field is nothing but an intense space, in terms of power where work is done or needed to be done upon in presence of an electrically charged particle depending on the nature of the charged particle.
A positive charge lacks electrons, where as a negative charge has excess electrons. What about the phenomenon of attraction of a neutral particle by a charged particle, because we can understand the phenomenon of attraction and repulsion between oppositely charged particles and same charged particles respectively, but how neutrally charged particles get attracted by charged particles. This can be explained by electrostatic induction
. The word induction itself explains a lot, it means action which is not the result of direct contact. To explain the above explained phenomenon, we can say that when a neutral body is brought near the charged body, due to influence of static electric field, free electrons inside the neutral body either come nearer to the charged body or go away from charged body depending upon the nature of charge in the charged body. If the charged body is positive, free electrons of the neutral body come nearer to the charged body and if the charged body is negative, the free electrons go away from the charged body. Thus, opposite charge is induced in the neutrally charged body near to the charged body and same charge on the opposite side. In this way, the portion of the neutral body nearer to the charged body is induced by opposite static charge and hence it would be attracted by charged body. We can understand the phenomenon more accurately by a diagram.