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hmalkan
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We know that the electrical current is scalar. Also we know that a scalar hasn't got a direction but electric current has got a direction. I've confused! Please help me..
hmalkan said:We know that the electrical current is scalar. Also we know that a scalar hasn't got a direction but electric current has got a direction. I've confused! Please help me..
confinement said:[tex]\vec{i} = A \vec{j} [/tex]
where A is the area.
jtbell said:The current density [itex]\vec J[/itex] is a vector, but the current I through a given surface is a scalar, as can be seen from the relationship between the two:
[tex]I = \int{\vec J \cdot d \vec a}[/tex]
When you're calculating e.g. the magnetic force on a current-carrying wire, the directionality of the current is properly associated with the length of the wire rather than with the current itself:
[tex]\vec F = I \vec l \times \vec B[/tex]
for a straight wire segment and uniform [itex]\vec B[/itex], or
[tex]\vec F = I \int {d \vec l \times \vec B}[/tex]
otherwise. This assumes that [itex]\vec B[/itex] doesn't vary significantly over the cross-section of the wire. If it does, then you have to calculate the force by using the current density and integrating over the volume of the wire:
[tex]\vec F = \int {(\vec J \times \vec B) dV}[/tex]
hmalkan said:I don't understand what [itex]\vec B[/itex] stands for.
hmalkan said:http://ecx.images-amazon.com/images/I/41VHYYJB0KL._SL160_.jpg
This is my book. It says electric current is a scalar at the heading of chapter 2.
Electric current is the flow of electric charge through a conductive material, such as a wire. It is measured in units of amperes (A).
Yes, electric current has a direction. It flows from a higher potential to a lower potential, similar to the flow of water from a higher elevation to a lower elevation.
The direction of electric current is determined by the direction of the flow of positive charge. This is opposite to the direction of the flow of electrons, which are negatively charged particles.
The direction of electric current is typically represented by an arrow pointing in the direction of the flow of positive charge. Alternatively, it can also be represented by the conventional current flow, which assumes that current flows from positive to negative.
Yes, the direction of electric current can change. In alternating current (AC) circuits, the direction of current changes periodically, while in direct current (DC) circuits, the direction remains constant. Additionally, the direction of current can also be changed by using electronic components such as diodes and transistors.