: 1.Please give the definitions of electric and magnetic dipole ρ and μ. : (Indicate their direction)(10%) An electric dipole ρ consists of two particles with charges of equal magnitude q but opposite sign, separated by a small distance d. Their dipole moment has magnitude qd and points from the negative charge to the positive charge. Since there are no magnetic charge, all magnets have dipole fields. These dipoles behave exactly like electric dipoles in electric field. We define the magnetic dipole of a flat current coil as μ. Vector μ = N*i*A*^n, where N is the number of turns in the coil, i is the current through the coil, and A is the area enclosed by each turn of the coil, and ^n is the unit vector normal to the surface enclosed by the coil with orientation chosen so that when the thumb of your right hand points in the direction of ^n your fingers curl in the direction i flows. --

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