In the link given below, i found a paragraph, which i had given below the link
http://electron9.phys.utk.edu/phys136d/modules/m6/current.htm
The current density is a vector. It represents the amount of net charge that crosses a unit area perpendicular to the flow per second. If just as many negative as positive charges move across a unit area in the same direction per second, then the current density is zero. If <v> = 0 and only positive charges are moving, then the direction of the current density is the direction of the velocity of the positive charges. In ordinary conductors the positive charges have zero average velocity and only the negative charges are moving. Then the direction of the current density is opposite to the direction of the velocity of the negative charges, as shown in the diagram on the right.
<v> > average velocity of negative charges.
Revered members,
Why direction of current density is opposite to the direction of the velocity of negative charges when <v+> = 0?
When <v> = 0, the direction of current density is along the velocity of positive charges, similarly the direction of current density should be along velocity of negative charges, when
<v+> = 0
http://electron9.phys.utk.edu/phys136d/modules/m6/current.htm
The current density is a vector. It represents the amount of net charge that crosses a unit area perpendicular to the flow per second. If just as many negative as positive charges move across a unit area in the same direction per second, then the current density is zero. If <v> = 0 and only positive charges are moving, then the direction of the current density is the direction of the velocity of the positive charges. In ordinary conductors the positive charges have zero average velocity and only the negative charges are moving. Then the direction of the current density is opposite to the direction of the velocity of the negative charges, as shown in the diagram on the right.
<v> > average velocity of negative charges.
Revered members,
Why direction of current density is opposite to the direction of the velocity of negative charges when <v+> = 0?
When <v> = 0, the direction of current density is along the velocity of positive charges, similarly the direction of current density should be along velocity of negative charges, when
<v+> = 0
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