Introduction:
Current and current density are two important concepts in the field of physics. Both of them are related to the flow of electric charge in a conductor. However, they are different in terms of their units and properties. In this response, we will discuss the differences between current and current density and explain why current is a scalar quantity while current density is a vector quantity.

What is Current?
Current is defined as the rate of flow of electric charge in a conductor. It is a scalar quantity that is measured in amperes (A). The direction of current flow is taken as the direction of the flow of positive charges. Current can be calculated using the following formula:

I = Q/t

Where I is the current, Q is the amount of charge flowing through the conductor in a given time t.

What is Current Density?
Current density is defined as the amount of current flowing through a unit area of a conductor. It is a vector quantity that is measured in amperes per square meter (A/m²). The direction of current density is perpendicular to the surface of the conductor. Current density can be calculated using the following formula:

J = I/A

Where J is the current density, I is the current flowing through the conductor, and A is the cross-sectional area of the conductor.

Why Current is a Scalar Quantity and Current Density is a Vector Quantity?
Current and current density are different in terms of their properties. Current is a scalar quantity because it has only magnitude and no direction. It is the amount of charge flowing through a conductor per unit time. On the other hand, current density is a vector quantity because it has both magnitude and direction. It is the amount of current flowing through a unit area of a conductor, and its direction is perpendicular to the surface of the conductor. Therefore, current density is a vector quantity.

Conclusion:
In conclusion, current and current density are two important concepts in the field of physics. Current is a scalar quantity that represents the rate of flow of electric charge in a conductor, while current density is a vector quantity that represents the amount of current flowing through a unit area of a conductor. The direction of current flow is taken as the direction of the flow of positive charges, while the direction of current density is perpendicular to the surface of the conductor.

Because current did not follow law of algabric vector but current density follow it