Question

Mention the two special features of a clinical thermometer.

Answer 1

Hint: The clinical thermometer which is also known as the Fahrenheit scale thermometer, is widely utilized for the body temperature measurement when they are unwell. This is also called a doctor’s thermometer.

Complete step by step answer:
A clinical thermometer usually consists of a cylindrical bulb with mercury and a capillary tube is finely fixed to this setup.
The two major features of a clinical thermometer are its calibration as well as its constriction.
We know that the temperature of the human body varies from $95^{\circ}F$ to $110^{\circ}F$. The thermometer is calibrated in such a way that it is capable of accommodating this range of temperature. Here, each degree is further divided to five smaller divisions which help in generating a more accurate value. The temperature value of $98.4^{\circ}F$ is emboldened because it is the average temperature of a healthy man. Hence, we can check the well-being of a person using this scale.

The second feature is the constriction of a thermometer, that is, there exists a narrow band in the capillary tube in the neck of the thermometer or very close to the bulb and this is due to the constriction property. This is mainly done to ensure that the mercury does not drop back to the previous state in between taking the reading of a person. As the temperature increases, the mercury pushes over the constriction due to the force of expansion.

Note:
Mercury is commonly used in thermometers because it is the only metal that exists as a liquid in room temperature. It has a high value of coefficient of expansion and a high boiling point as well. Hence, it is apt to measure high temperatures and give an accurate value. Each degree is further divided into five smaller divisions which help in generating a more accurate value.