Unpolarized light of intensity `I_(0)` is incident on surface of a block of glass at brewster's angle. In that case, which one of the following statements is true-

Options

A. transmitted light is partially polarized with intensity `(I_(0))/(2)`
B. transmitted light is completely polarized with intensity less than `(I_(0))/(2)`
C. reflected light is partially polarized with intensity `(I_(0))/(2)`
D. reflected light is completely polarized with intensity less than `(I_(0))/(2)`

Answer

To solve the problem, we will analyze the situation of unpolarized light incident on the surface of a block of glass at Brewster's angle. We will derive the necessary conclusions step by step.

### Step-by-Step Solution:

1. **Understanding Brewster's Angle**:
Brewster's angle (θ_B) is defined as the angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection. At this angle, the reflected light is completely polarized.

2. **Incident Light Characteristics**:
The light incident on the glass surface is unpolarized and has an intensity of \( I_0 \).

3. **Reflection and Transmission**:
When unpolarized light strikes the surface at Brewster's angle, part of the light is reflected and part is transmitted into the glass. The reflected light is polarized.

4. **Intensity of Reflected Light**:
At Brewster's angle, the intensity of the reflected light \( I' \) is given by:
\[ I' = \frac{I_0}{2} \]
However, since the reflected light is completely polarized, the intensity of the reflected light is actually less than \( \frac{I_0}{2} \).

5. **Intensity of Transmitted Light**:
The intensity of the transmitted light \( T \) can be calculated using the conservation of energy principle:
\[ T = I_0 - I' \]
Since \( I' < \frac{I_0}{2} \), it follows that \( T > \frac{I_0}{2} \).

6. **Conclusion**:
The correct statement regarding the incident unpolarized light at Brewster's angle is that the reflected light is completely polarized and has an intensity less than \( \frac{I_0}{2} \).

### Final Answer:
The reflected light is completely polarized with intensity less than \( \frac{I_0}{2} \).