A positive point charge Q is brought near an isolated metal cube then what will happen to the charge of cube?

Options

A. The cube becomes negatively charged.
B. The cube becomes positively charged.
C. The interior becomes positively charged and the surface becomes negatively charged.
D. The interior remains charge free and the surface gets onouniform charge distribution.

Answer

To solve the problem of what happens to the charge of an isolated metal cube when a positive point charge \( Q \) is brought near it, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the System**:
- We have an isolated metal cube, which is a conductor, and we are bringing a positive point charge \( Q \) close to it.

2. **Effect of the Positive Charge**:
- When the positive charge \( Q \) is brought near the metal cube, it creates an electric field around itself. This electric field influences the charges within the metal cube.

3. **Induction of Charges**:
- Due to the electric field from the positive charge \( Q \), the free electrons in the metal cube will be attracted towards the side of the cube that is closest to the positive charge. This results in a negative charge accumulating on that side of the cube.

4. **Distribution of Charges**:
- As electrons move towards the side of the cube nearest to the positive charge, the opposite side of the cube will become positively charged due to the deficiency of electrons there. Thus, we have:
- Negative charge \( -Q \) on the side of the cube closest to the positive charge.
- Positive charge \( +Q \) on the opposite side of the cube.

5. **Net Charge of the Cube**:
- Despite the separation of charges within the cube, the total charge of the cube remains unchanged. Since the cube was initially neutral (isolated), the net charge of the cube remains zero. The positive and negative charges induced on the surfaces of the cube balance each other out.

6. **Conclusion**:
- Therefore, when a positive point charge \( Q \) is brought near an isolated metal cube, the cube will exhibit induced charges on its surfaces, with negative charge on the side facing the positive charge and positive charge on the opposite side, while the net charge of the cube remains zero.

### Summary of Findings:
- The cube remains electrically neutral overall, but charge separation occurs due to induction.