Name the instrument used to measure temperature using the radiation emitted from the body ?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an instrument that measures temperature based on the radiation emitted from a body. This involves understanding the concept of thermal radiation and how it can be used to gauge temperature.

2. **Identifying the Instruments**: There are specific instruments designed to measure temperature using thermal radiation. The two main types mentioned are:
- **Infrared Thermometer**: This is a common device used to measure the temperature of a body by detecting the infrared radiation emitted from it. It is widely used in medical settings, especially during health crises like the COVID-19 pandemic.
- **Pyrometer**: This is another type of thermometer used primarily for industrial applications. It measures high temperatures by detecting the thermal radiation emitted from hot objects.

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