The correct option is 1 only
Explanation
Electric current is defined as the rate of flow of electric charge through a cross-section of a conductor. In metallic conductors, the flow of current is governed by the movement of free electrons under the influence of an electric field established by a potential difference.
Statement-wise Analysis
- Statement 1 is Correct: In metallic conductors, the atoms form a lattice structure where the valence electrons are loosely bound and can move freely throughout the metal. These free electrons act as the mobile charge carriers. When a potential difference is applied across the wire, these electrons drift towards the positive terminal, constituting an electric current.
- Statement 2 is Incorrect: By convention, the direction of electric current is taken as the direction of the flow of positive charges, which is from the positive terminal to the negative terminal of the source. However, electrons are negatively charged and flow from the negative terminal to the positive terminal. Therefore, the direction of conventional current is opposite to the direction of electron flow.
- Statement 3 is Incorrect: For a continuous flow of current, charge carriers must be able to move in a continuous loop from one terminal of the source back to the other. If the conducting path is broken (an open circuit), the flow of charge carriers stops immediately. A closed conducting path is a fundamental requirement for a continuous current.
Key Takeaway
Key Takeaway: In metallic conductors, current is carried by electrons flowing from negative to positive potential, whereas the conventional current direction is historically defined as flowing from positive to negative potential.