Define electric current. Explain the difference between electron current and conventional current?
Answers
Answer:
Current is the flow of electrical charge carriers like electrons. Current flows from negative to positive points. The SI unit for measuring electric current is the ampere (A). One ampere of current is defined as one coulomb of electrical charge moving past a unique point in a second.An electric current is the rate of flow of electric charge past a point or region. An electric current is said to exist when there is a net flow of electric charge through a region. In electric circuits this charge is often carried by electrons moving through a wire.
The conventional current is defined as charge per unit time transported in a certain direction. The current direction is the direction of positive charge movement. A positive current is also negative charge per unit time moving in opposite direction to the corresponding positive charge. In conventional current, the type of charge carrier is irrelevant. It can also be produced by positive and negative charge carriers at the same time moving in opposite directions like currents in electrolytes or ionized gases. Electronic current is current produced by the movement of negatively charged electrons. This is usually the case in metals. When electrons produce a positive current in a certain direction, this means they are actually moving in the opposite direction.
Electric current can be either positive or negative, but conventional current is always positive.
• The conventional current for an electron flow is positive, whereas the electrical current is .
• For a flow of positive charges, both the electric current and the conventional current are the same.
• Since almost every electrical circuit uses an electron flow, it can be safely stated that the conventional current = – electrical current.
• In conventional current, the flow of electrons is assumed as a flow of protons on the opposite direction.
In conventional current, electrons flow from positive to negative terminal whereas In electric current, current flows from negative to positive terminal of a battery.
Explanation:
The electric current is the net amount of electric charge that passes through any crosssectional area of the conductor in unit time.
OR
Rate of flow of electric charges in particular direction.
In earlier times, when electrons were not known, it was thought that the electric current is constituted due to the flow of positive charges.
After the discovery of the electron, it was realized that the motion of electrons is responsible for the flow of electric current, which is called electron current.
As per the old convention, the direction of electric current is taken as the direction of the flow of positive charges. This flow is known as conventional current.
The direction of conventional current is still followed even after the discovery of electron. Hence, the conventional current is in the direction opposite to the direction of the flow of electrons.
As shown in figure 12.1, the flow of electron current in the conducting wire AB is taken from B to A, but the direction of the conventional current is considered from A to B.