Dipole

#VishnuPhysics An electric dipole is tagged as a pair of objects which possess equal & opposite charges, parted by a significantly small distance. Let us take two charges having equal magnitude ‘Q’, which are separated by the distance ‘D’. Here we assume the first charge to be negative, while the second charge stays positive. You can call this particular combination as an electric dipole. Hence, we can state that an electric dipole is formed due to the grouping of equal & opposite charges when separated by an assured distance. Atoms as a whole are electrically neutral in their ground state. We know that atoms have an equal amount of positive and negative charges. Similar to atoms molecules are also neutral but they also have an equal amount of positive and negative charges. Now when in a system, the algebraic sum of all the charges is zero it does not necessarily mean that the electric field produced by the system is zero everywhere. This makes the study of electric dipoles important for the electrical phenomenon in the matter. The matter which is made up of atoms and molecules is electrically neutral. If the center of mass of positive charges coincides with that of negative charges then the molecule behaves as a non-polar molecule. On the other hand, if the center of mass of positive charges does not coincide with that of negative charges then the molecule behaves as a polar molecule. These polar molecules have permanent dipole moments. These dipole moments are randomly oriented in the absence of an external electric field. If we place material with polar molecules in the external electric field then these molecules align themselves in the direction of the field. This results in the development of a net dipole moment. This particular piece of material is said to be polarized. So the study of dipole and dipole moments gives a measure of the polarization of a net neutral system. The study of dipole moments measures the tendency of a dipole to align with an external electric field. Question 1: What is the difference between electric dipole and electric dipole moment? Answer: Electric dipole is just the separation of two equal and opposite charges separated a small distance whereas electric dipole moment measures the strength of an electric dipole. Electric dipole moment occurs due to the existence of an electric dipole. It measures the electric polarity of the system of charges. Question 2: How is electric dipole calculated? Answer: We do not calculate electric dipole. An electric dipole is just a formation of two equal and opposite charges. We rather calculate its dipole moment. Question 3: What is the significance of electric dipole? Answer: Please refer to Physical significance of Electric Dipole Question 4: Is electric dipole moment scalar or vector? Answer: It is a vector quantity. Question 5: Why electric dipole moment is from negative to positive? Answer: This is purely a matter of convention. If you want you can define it another way around but it might lead to change in the equation for energy, torque, etc..