What constitutes current in a metal wire ?

Options

A. Electrons
B. Protons
C. Atoms
D. Molecules

Answer

**Step-by-Step Solution:**

1. **Understanding Current**: Current is defined as the flow of electric charge. In a metal wire, this charge is primarily carried by electrons.

2. **Identifying Charge Carriers**: In metals, the charge carriers are free electrons. Metals have a structure that allows some of their electrons to move freely, which is essential for conducting electricity.

3. **Direction of Electron Flow**: When a potential difference (voltage) is applied across a metal wire, electrons move from the region of higher potential (negative terminal) to the region of lower potential (positive terminal). This movement of electrons constitutes an electric current.

4. **Conclusion**: Therefore, the current in a metal wire is due to the movement of electrons from high potential to low potential.

**Final Answer**: Current in a metal wire is constituted by the movement of electrons.

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