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Question
The following diagrams illustrate three situations involving thermometers which are labeled A, Band C. In each situation the thermometers indicate different readings.
(i) What do you expect the approximate reading of the thermometer B and C would be? Give a reason for your answer.
(ii) How would the readings of A and B help you in calibrating a thermometer?

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Solution

(i) The temperature of steam and boiling water Is equal so the reading of thermometer is the same. But due to the addition of salt boiling point of water elevates so the reading of thermometer would be slightly higher than the boiling point of water i.e 100° C.
(ii) The addition of salt boiling point of water increases so thermometer has to measure temperature for a wider range and thus it helps in the calibration of the thermometer.
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