Choose the correct option for each question. There is only one correct response for each question.
What happens to the meteorites when they enter Earth's atmosphere?

Options

A. They melt due to heat
B. They bounce back to space
C. They start orbiting around the Earth
D. They burn due to the heat generated by friction.

Answer

To solve the question "What happens to the meteorites when they enter Earth's atmosphere?", we can analyze the options provided and determine the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding Meteorites**:
- Meteorites are fragments of rock or metal that originate from space and enter the Earth's atmosphere.

2. **Entering the Atmosphere**:
- When meteorites enter the Earth's atmosphere, they travel at extremely high speeds, often tens of thousands of kilometers per hour.

3. **Friction with Air**:
- As the meteorites move through the atmosphere, they encounter air resistance. This interaction creates friction between the meteorite and the air molecules.

4. **Heat Generation**:
- The friction generated by the meteorite moving at high speeds through the atmosphere causes significant heat to build up.

5. **Outcome of Heat**:
- The intense heat produced due to friction can cause the meteorite to burn up, resulting in a bright streak of light commonly referred to as a "shooting star."

6. **Evaluating the Options**:
- **Option 1**: They melt due to heat - This is partially true, but it doesn't fully capture the process.
- **Option 2**: They bounce back to space - This is incorrect; meteorites do not bounce back.
- **Option 3**: They start orbiting the Earth - This is also incorrect; they do not enter orbit.
- **Option 4**: They burn due to the heat generated by friction - This is the correct option, as it accurately describes the phenomenon.

### Conclusion:
The correct answer is **Option 4**: They burn due to the heat generated by friction.

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