Question

What is represented by the electric current?
(A) Charge per unit volume.
(B) Charge per unit time.
(C) Charge per unit area.
(D) Both A and B.

Answer 1

Hint: Electric current is the flow of electrons in an electric current. The magnitude of electric current is measured in coulombs per second.

Complete Step by Step Solution
Electric current is defined as the rate of flow of negative charges of the conductor. In other words, the continuous flow of electrons in an electric circuit is called an electric current. The conducting material consists of a large number of free electrons which move from one atom to the other at random.
An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in plasma. It is the rate of charge flow past a given point in an electric circuit. It is the charge per unit time.
The SI unit of electric current is Ampere and is denoted by the letter A. Ampere is defined as one coulomb of charge moving past a point in one second. If there are $ 6.241 \times {10^{18}} $ electrons flowing through our frame in one second then the electrical current flowing through it is ‘One Ampere.’
Thus, the correct answer is Option A.

Note
Electrons are minute particles that exist within the molecular structure of a substance. Sometimes, these electrons are tightly held, and the other times they are loosely held. When electrons are loosely held by the nucleus, they are able to travel freely within the limits of the body. Electrons are negatively charged particles hence when they move a number of charges moves and we call this movement of electrons as electric current. It should be noted that the number of electrons that are able to move governs the ability of a particular substance to conduct electricity. Some materials allow current to move better than others. Based on the ability of the material to conduct electricity, materials are classified into conductors and insulators.
Conductors are materials that allow the free flow of electrons from one particle to another. Conductors allow for charge transfer through the free movement of electrons. The flow of electrons inside the conducting material or conductor generates an electric current. The force that is required to drive the current flow through the conductor is known as voltage.
Examples of conductors include the human body, aqueous solutions of salts and metals like iron, silver and gold.
Insulators are materials that restrict the free flow of electrons from one particle to another. The particles of the insulator do not allow the free flow of electrons; subsequently, charge is seldom distributed evenly across the surface of an insulator.
Examples of insulators include plastic, wood and glass.