To Find:The reason for the decrease of the mercury level when the thermometer is first placed in warm water.
Explanation of Solution
Introduction:
Coefficient of expansion is the ratio of the length/volume increase in body by rise in temperature to length, area or volume of the body, at some defined temperature and constant pressure.
Mercury level decreases when the thermometer is first placed in warm water.This is because the thermometer's glass initially expands while the mercury remains cold.Therefore,mercury remains at the same level while the glass container volume increases resultingin decreaseof the mercury level. The mercury then starts to expand when heated and the correct temperature appears.
Conclusion:
Due to positive expansion coefficient, the glass bulb expands. The mercury level appears to decrease.
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Chapter 20 Solutions
Physics for Scientists and Engineers
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