Which part of the spectrum of electromagnetic radiation is used for aircraft navigation?

Options

A. Ultraviolet rays
B. Radiowaves
C. X-rays
D. Infrared waves

Explanation

To solve the question about which part of the spectrum of electromagnetic radiation is used for aircraft navigation, we can follow these steps:

### Step 1: Identify the options given
The options provided in the question are:
1. Ultraviolet rays
2. Radio waves
3. X-rays
4. Infrared waves

### Step 2: Understand the purpose of aircraft navigation
Aircraft navigation systems are designed to determine the position and direction of an aircraft. This is crucial for safe and efficient flight operations.

### Step 3: Analyze the characteristics of each option
- **Ultraviolet rays**: These have shorter wavelengths and are primarily used in applications like sterilization and fluorescence. They are not suitable for long-range navigation.
- **Radio waves**: These have longer wavelengths and can travel long distances. They are commonly used in communication and radar systems.
- **X-rays**: These are high-energy waves used mainly in medical imaging and not suitable for navigation.
- **Infrared waves**: These are used in thermal imaging and remote controls but are not typically used for navigation.

### Step 4: Determine the correct option
Since radar systems, which are integral to aircraft navigation, operate using radio waves, the correct answer is:

**Radio waves (Option 2)**

### Step 5: Conclusion
Radio waves are the part of the electromagnetic spectrum used for aircraft navigation due to their ability to travel long distances and penetrate various atmospheric conditions.

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