When current flows through copper wire, current density J, electric field E and motion of electrons have directions such that

Options

A. J and E are In opposite directions
B. motion of electrons and E are In opposite directions
C. J and motion of electrons ore In the same direction.
D. J, E and motion of electrons are In same direction.

Answer

To solve the problem, we need to analyze the relationships between current density (J), electric field (E), and the motion of electrons in a copper wire when current flows through it.

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have a copper wire connected to a battery. The positive terminal of the battery is connected to one end of the wire, and the negative terminal is connected to the other end.

2. **Direction of Electric Field (E)**:
- The electric field (E) in the wire is directed from the positive terminal to the negative terminal of the battery. This means that the electric field points in the direction of conventional current flow.

3. **Direction of Current Density (J)**:
- Current density (J) is defined as the amount of current flowing per unit area of the wire. By convention, current flows in the same direction as the electric field. Therefore, the direction of current density (J) is also from the positive terminal to the negative terminal.

4. **Direction of Electron Motion**:
- Electrons are negatively charged particles. They move in the opposite direction to the electric field due to the attractive force exerted by the positive terminal of the battery. Thus, while the electric field and current density are directed from positive to negative, the motion of electrons is directed from negative to positive.

5. **Summary of Directions**:
- **Electric Field (E)**: From positive to negative (→)
- **Current Density (J)**: From positive to negative (→)
- **Motion of Electrons**: From negative to positive (←)

6. **Conclusion**:
- From the above analysis, we can conclude that the current density (J) and electric field (E) are in the same direction, while the motion of electrons is in the opposite direction.

### Final Answer:
- The correct relationship is that the current density (J) and electric field (E) are in the same direction, while the motion of electrons is in the opposite direction.