What is the function of 'kink' in a clinical thermometer ?

Explanation

### Step-by-Step Solution:

1. **Understanding the Clinical Thermometer**: A clinical thermometer is a device used to measure body temperature. It typically contains a liquid (mercury or alcohol) that expands and rises in a narrow tube when heated.

2. **Identifying the Kink**: The 'kink' in a clinical thermometer is a constriction or a slight bend in the tube that holds the liquid. It is usually located just above the bulb where the liquid is stored.

3. **Function of the Kink**: The primary function of the kink is to prevent the liquid (mercury or alcohol) from falling back down the tube immediately after the thermometer is removed from the body.

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