If polaroids are to be used to avoid glares of in coming light then

Options

A. visibility will decrease
B. transmittivity of windshield will decrease
C. vehicles will move slowly
D. cost will increase

Answer

To solve the question regarding the use of polaroids to avoid glares from incoming light, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of Polaroids**:
- Polaroids are optical filters that allow light waves of a specific polarization to pass through while blocking others. This property is used to reduce glare from surfaces like water or roads.

2. **Analyze the Situation**:
- In the context of a car windshield made of polaroids, incoming light from the sun or other sources may be polarized. The polaroids will selectively absorb the polarized light that causes glare.

3. **Evaluate the Options**:
- **Option 1: Visibility will decrease**: This is incorrect. While some light is absorbed, the overall visibility is not significantly affected because most of the light is transmitted.
- **Option 2: Part of the sun is very cool will move slowly**: This option does not relate to the use of polaroids and is irrelevant.
- **Option 3: Cost will increase**: This is also incorrect. Polaroids can be made from inexpensive synthetic materials, so the cost may not necessarily increase.
- **Option 4: Transmittivity of the windshield will decrease**: This is correct. Since polaroids absorb certain polarized light waves, the overall transmittivity (the amount of light that passes through) of the windshield will decrease.

4. **Conclusion**:
- The correct answer is that the transmittivity of the windshield will decrease when polaroids are used to avoid glares from incoming light.

### Final Answer:
The transmittivity of the windshield will decrease when polaroids are used to avoid glares of incoming light.

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