Earth's atmosphere is transparent for

Options

A. only the visible light
B. only the X-rays
C. only the y-rays
D. visible light and microwaves

Explanation

To determine which types of electromagnetic radiation Earth's atmosphere is transparent to, we will analyze the wavelengths of different types of radiation and how they interact with the atmosphere.

### Step-by-Step Solution:

1. **Identify the Wavelengths of Different Radiations**:
- X-rays: Approximately 0.1 to 10 nanometers (average taken as 10 nm).
- Gamma rays: Approximately 10 picometers (10^-12 meters).
- Visible light: Ranges from 400 to 700 nanometers.
- Microwaves: Ranges from 1 millimeter (1 mm) to 1 meter (1 m).

2. **Understand the Absorption Characteristics of the Atmosphere**:
- The Earth's atmosphere has different layers, including the ozone layer, which absorbs certain wavelengths of electromagnetic radiation.
- The ozone layer primarily absorbs wavelengths below 350 nanometers. This means:
- X-rays (10 nm) and gamma rays (10 pm) are absorbed since they are both below 350 nm.
- Visible light (400-700 nm) is not absorbed as it is above 350 nm.
- Microwaves (1 mm to 1 m) are also not absorbed as they have much longer wavelengths than 350 nm.

3. **Determine Which Radiations are Transparent**:
- Since X-rays and gamma rays are absorbed by the atmosphere, they are not transparent.
- Visible light and microwaves, however, are not absorbed by the atmosphere, making them transparent.

4. **Select the Correct Answer**:
- The question asks for which types of radiation the Earth's atmosphere is transparent. Given our analysis, the correct answer is that the Earth's atmosphere is transparent to:
- **Visible light and microwaves**.

### Final Answer:
The Earth's atmosphere is transparent for **visible light and microwaves**.

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