Q16 of 20 Page 24

Why is it advised not to hold the thermometer by its bulb while reading it?

Bulb in the thermometer contains mercury so when we hold the thermometer by its bulb then our body temperature which is normally 37°C is enough to expand mercury (Yes mercury expands on heating although here we are not heating but it is very sensitive to temperature) as a result the shape of the thermometer gets distorted and we get faulty reading.


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