Question

Temperature of boiling water cannot be measured by ______
(A). Lab thermometer
(B). Clinical thermometer
(C). Neither A nor B
(D). None

Answer 1

Hint: For a thermometer to be able to measure the temperature of boiling water, the thermometer must have an upper range that is higher than the boiling point of water. Clinical thermometers are usually used to measure the temperature of the human body.

Complete step by step answer:
If a thermometer has to measure the boiling temperature of water, it must have an upper range on its scale that is equal to or greater than the boiling temperature of water. The boiling temperature of water is ${{100}^{0}}C$.
A clinical thermometer is usually used to measure the temperature of the human body. Hence, it is calibrated to measure the general temperature of the human body. The scale on a clinical thermometer generally ranges between ${{35}^{0}}C$ and${{42}^{0}}C$. The normal human body temperature is ${{37}^{0}}C$. Hence, the clinical thermometer is good for measuring changes in the temperature of the human body. However, its upper limit is much lesser than the boiling temperature of water $\left( {{100}^{0}}C \right)$ and hence, it cannot be used for that purpose.
For measuring the boiling temperature of water, a laboratory thermometer is more suited since its range is from $-{{10}^{0}}C$ to ${{110}^{0}}C$ in general. Hence, it can easily measure the boiling temperature of water $\left( {{100}^{0}}C \right)$.
Hence, the correct answer is B) Clinical thermometer.

Note: Students should understand that each thermometer is developed keeping its purpose in mind. Therefore, even though a lab thermometer can be used to measure the changes in human body temperature (since it has the range to do so), it is not used for that purpose, since the calibrations are done in such a way such that it would be more difficult to read the changes in the human body temperature than reading it on a clinical thermometer that is specifically designed for the ease of use and calibrated to get a good reading even for a minute change in the human body temperature.