Mark the correct option

Options

A. Gauss law is valid fro unsymmetrical charged distributions
B. Gauss law is valid only for charge palced in vacuum
C. The electric field is calculated by Gauss law is the field due to the charges outside the Gauss law is the field due to the charges outside the Gaussian surface.
D. The flux of the electric field through a closed surface due to all the charges is equal to the flux due to the charges enclosed by the surface.

Answer

To solve the question regarding Gauss's law and to mark the correct option, we will go through the following steps:

### Step 1: Understand Gauss's Law
Gauss's law states that the electric flux (Φ) through a closed surface is proportional to the charge (Q) enclosed within that surface. Mathematically, it is expressed as:
\[ \Phi = \frac{Q_{\text{in}}}{\epsilon_0} \]
where \( \epsilon_0 \) is the permittivity of free space.

### Step 2: Analyze the Options
We need to evaluate the given options based on our understanding of Gauss's law:

1. **Option A**: "Gauss's law is valid only for unsymmetrical charge distribution."
- This statement is incorrect. Gauss's law is valid for both symmetrical and unsymmetrical charge distributions.

2. **Option B**: "Gauss's law is valid only in vacuum."
- This statement is also incorrect. Gauss's law holds true in any medium, not just in vacuum.

3. **Option C**: "The electric field calculated by Gauss's law is due to the charge outside the Gaussian surface."
- This statement is incorrect. The electric field calculated using Gauss's law is due to the charge enclosed within the Gaussian surface, not outside.

4. **Option D**: "The flux of the electric field through a closed surface is equal to the charge enclosed by the surface."
- This statement is correct as it directly reflects the essence of Gauss's law.

### Step 3: Conclusion
After analyzing all the options, we conclude that the correct option is:
**Option D**: "The flux of the electric field through a closed surface is equal to the charge enclosed by the surface."