Thermoplies are used for the detection of

Options

A. IR-waves
B. UV-rays
C. X-rays
D. `gamma`rays

Answer

**Step-by-Step Solution:**

1. **Understanding Thermopiles:**
- Thermopiles are devices that convert thermal energy (heat) into electrical energy. They are made up of multiple thermocouples connected in series or parallel.

2. **Function of Thermopiles:**
- The primary function of thermopiles is to measure temperature. They do this by detecting the infrared radiation emitted by objects.

3. **Detection Mechanism:**
- Thermopiles work by sensing the infrared energy that is emitted from an object. The amount of infrared radiation corresponds to the temperature of the object.

4. **Identifying the Type of Waves Detected:**
- Since thermopiles measure temperature by detecting infrared radiation, they are specifically designed to detect infrared waves.

5. **Analyzing the Options:**
- The question provides four options:
1. IR waves
2. UV rays
3. X-rays
4. Gamma rays
- Based on the function of thermopiles, we can conclude that they are used for the detection of IR waves.

6. **Final Answer:**
- Therefore, the correct answer is Option 1: IR waves.

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