Question

The thermometer suitable to measure ${{2000}^{{}^\circ }}C$ is:
(A) Gas thermometer
(B) Mercury thermometer
(C) Vapour pressure thermometer
(D) Total radiation pyrometer

Answer 1

Hint Every thermometer has got its own limitations for measuring temperatures. So to answer this question we should be knowing the best suitable mentioned option, which fulfils the criteria to measure a temperature of ${{2000}^{{}^\circ }}C$. So the answer should begin with the description of the correct option among the mentioned ones.

Complete step by step answer
We should know that pyrometers which are also known as radiation thermometers are used in order to detect radiations from the hot bodies.
They can measure a temperature which is as high as ${{2000}^{{}^\circ }}C$. The total radiation pyrometer can measure the temperature of a specific body without even making any contact with the body and thus is suitable for the measurement of ${{2000}^{{}^\circ }}C$.
So we can say that the thermometer suitable to measure ${{2000}^{{}^\circ }}C$ is total radiation pyrometer.

Hence the correct option is option D.

Note We should know the principal behind the working of a total radiation pyrometer. So the basic principle of the pyrometer is that it always measured the body’s temperature by sensing the amount of heat or the radiation that is emitted from the body. But the pyrometer never comes in contact with the body. It will also record the temperature level that will depend on the intensity of the emitted radiation from the body.
The total radiation pyrometer will receive the radiation from a specific body which will include both the visible and the invisible radiations. The main thing that the total radiation pyrometer consists of is a receiving element and a device to measure the amount of radiation that is received.
The main difference between a thermometer and a pyrometer is that pyrometers are especially designed to measure very high temperatures.