Charges, current, and Electric Field direction?

In summary, positive charges drift in the direction of electric field and negative charges drift in the direction opposite of electric fields. This is because the direction of electric field is from positive charge to negative charge. Additionally, current density is in the direction of current if the charge is positive, and opposite if the charge is negative. This is due to the fact that current density is equal to current divided by area, and if the current is due to positive charges, the current density will also be positive and vice versa. It is also important to note that electric field lines are directed outward in the case of positive charges and inward in the case of negative charges.
  • #1
lu6cifer
16
0
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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  • #2
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
 
  • #3
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
 

1. What is the difference between charge and current?

Charge refers to the fundamental property of matter that causes it to experience a force in an electric field. Current, on the other hand, is the flow of electric charge through a conductive material. In simpler terms, charge is a static property while current is a dynamic flow of charge.

2. How is charge measured?

Charge is measured in units of Coulombs (C). One Coulomb is equivalent to the charge of 6.24 x 10^18 electrons. Charge can also be measured as a ratio of the electric field force acting on a charged particle to the charge of the particle itself.

3. What is the direction of an electric field?

The direction of an electric field is defined as the direction in which a positive test charge would move when placed in the field. This means that the direction of the electric field is always from positive charges to negative charges.

4. How does current flow in a circuit?

In a circuit, current flows from the positive terminal of a voltage source to the negative terminal, through the conductive material, and back to the positive terminal. This flow of current is due to the movement of negatively charged electrons.

5. How does the direction of an electric field affect the motion of charged particles?

The direction of an electric field determines the direction in which a charged particle will move. A positive charge will move in the same direction as the electric field, while a negative charge will move in the opposite direction. The magnitude of the electric field also affects the speed of the charged particle's motion.

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