When you have a fever, the temperature, the temperature is taken with the help of a thermometer. The bulb of the thermometer is normally placed under the tongue or in the armpit or groin.
What’s the reason?
For a correct reading of body temperature, the bulb of the thermometer (which contains mercury) has to be in direct touch with the body’s surface.
If the thermometer is placed simply inside the mouth, it may not give a correct reading, as the bulb may not be in contact with the tongue. In such a case the temperature recorded will be that of the air and saliva in the mouth.
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