Question

Electric current consists of a flow of positive charges or negative charges. Explain.

Answer 1

Hint: The properties of electric potential have to be known to explain the directions of motion of a free positive charge as well as a free negative charge. Note that, the flow of electric current is considered equivalent to the flow of water from high level to low level. From this concept, the conventional direction of electric current is stated.

Complete step-by-step solution:
The point on a conductor or an element having high potential is considered as a positive point and the point on a conductor or an element having low potential is considered as a negative point. From the properties of electric potential, it is known that (1) if there is free positive charge in a conductor it will pass from high potential to low potential and, (2) if there is free negative charge in a conductor it will pass from low potential to high potential. Hence the direction of the positive charge and negative charge are opposite to each other.
The direction of the flow of the electric current is considered similar to the direction of the flow of water. As water flows from high level to low level, the electric current also flows from the high potential to low potential.
Hence, we can say the electric current consists of the flow of positive charges.

Note: In a metal conductor the current flows due to free electrons. Since the electron is negatively charged, the electrons flow from the low potential to high potential which is clearly opposite to the flow of electric current.
There are two types of current shown based on the direction. Direct current (DC) and Alternating current (AC). DC is the current that flows in a conductor with an unchanged direction and in a continuous manner. AC is the current that changes its direction at a certain interval.