Charges, current, and Electric Field direction?

AI Thread Summary
Positive charges drift in the direction of the electric field, while negative charges move in the opposite direction, which can lead to confusion depending on the source of the electric field. The generalization holds because the electric field direction is defined from positive to negative charges. Current density aligns with the charge type; it flows in the same direction as positive charges and opposite for negative charges. The electric field lines emanate outward from positive charges and inward toward negative charges. Understanding these principles clarifies the behavior of charges in electric fields.
lu6cifer
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My book says that positive charges drift in the direction of electric field, and negative charges drift in the direction opposite of electric fields

But wouldn't that depend on if the electric field was generated from a positive or negative charge? How can they just make a generalization like that?

And it also says that current density is in the direction of current if charge is positive, but opposite if charge is negative...why is that?
 
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the direction of electric field is from +ve charge to -ve charge
2nd ans current density=current/area if current is due to +ve charges current is +ve hence current density and vice versa
 
omkar13 said:
the direction of electric field is from +ve charge to -ve charge
2nd ans current density=current/area if current is due to +ve charges current is +ve hence current density and vice versa

i am also agree with this. also keep in mind that the electric field lines are directed outward in case of +ive charge while directed inward in case of -ive charge
 
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