Choose the correct alternative

Options

A. When plane polarised light passes through polaroid, it changes it changes its nature to linearly polarised
B. Refracted light, when light is incident at Brewster angle, in linearly polarised
C. Polarised light can be produced by scattering through `pi/2` in earth's atmosphere
D. Natural light from sun is polarised

Answer

To solve the question regarding the statements about polarized light, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement 1: When plane polarized light passes through a polaroid, it changes its nature to linearly polarized light.**
- **Analysis:** Plane polarized light is already linearly polarized light. When it passes through a polaroid, it retains its nature as plane polarized light. The only change that occurs is in intensity, not in the nature of the light.
- **Conclusion:** This statement is **false**.

2. **Statement 2: Refracted light when light is incident at Brewster's angle is linearly polarized.**
- **Analysis:** When unpolarized light is incident at Brewster's angle, the reflected light is completely polarized, but the refracted light is partially polarized. Therefore, the statement that refracted light is linearly polarized is incorrect.
- **Conclusion:** This statement is **false**.

3. **Statement 3: Polarized light can be produced by scattering through π/2 in Earth's atmosphere.**
- **Analysis:** When unpolarized sunlight is scattered by particles in the atmosphere, the light emitted in directions perpendicular to the incident light is polarized. This means that at an angle of π/2 (90 degrees) to the direction of propagation, the scattered light is indeed polarized.
- **Conclusion:** This statement is **true**.

4. **Statement 4: Natural light from the Sun is polarized.**
- **Analysis:** Natural sunlight is generally considered to be unpolarized. While certain conditions can lead to polarization (like scattering), sunlight itself is not inherently polarized.
- **Conclusion:** This statement is **false**.

### Final Summary:
- Statement 1: **False**
- Statement 2: **False**
- Statement 3: **True**
- Statement 4: **False**