The conventional direction of the current is from positive terminal to the negative terminal. Electrons are the negatively charged particles . They cannot move towards the negative terminal because like charges repel each other. They can move towards the positive terminal because unlike charges attract each other. So they will move in the opposite direction of current flow in the wire.
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**Introduction:**
In order to understand why the direction of electron flow is opposite to the direction of current flow in a wire, it is important to have a clear understanding of the concepts of current and electron flow.

**Current Flow:**
Current flow refers to the movement of electric charges in a conductor. It can be either positive charges (conventional current) or negative charges (electron flow). The conventionally accepted direction of current flow is from the positive terminal of a battery to the negative terminal. This convention was established before the discovery of the electron.

**Electron Flow:**
Electron flow refers to the movement of electrons within a conductor. Electrons are negatively charged particles that orbit the nucleus of an atom. When a voltage is applied across a wire, the electrons are set in motion, creating an electric current.

**The Role of Electrons in Current Flow:**
In a conductive material, such as a wire, electrons are loosely bound to their respective atoms and can move relatively freely. When a voltage is applied across the wire, an electric field is created which exerts a force on the free electrons, causing them to move.

**The Convention of Current Flow:**
The convention of current flow, established before the discovery of the electron, assumed that current flowed from the positive terminal to the negative terminal of a battery. This convention was based on observations of the flow of positive charges, which are found in abundance in ionic solutions.

**Opposite Direction of Electron Flow:**
Despite the convention of current flow being from positive to negative, the actual movement of electrons (electron flow) within a wire is in the opposite direction. This is because electrons are negatively charged particles and are repelled by the negative terminal of a battery and attracted to the positive terminal.

**Conclusion:**
In conclusion, the direction of electron flow within a wire is opposite to the direction of current flow. This is due to the convention established before the discovery of the electron, which assumed that current flowed from positive to negative. Electrons, being negatively charged, are repelled by the negative terminal and attracted to the positive terminal, causing them to move in the opposite direction.