The liquid column in a thermometer falls immediately after removing it from hot water because the liquid inside the thermometer contracts as it cools down. When the thermometer is in hot water, the liquid expands due to the heat, rising up the tube to show a higher temperature. Once it is removed from the heat source, the liquid cools and contracts, causing the column to fall. This change happens quickly as the temperature of the liquid adjusts to the surrounding environment.
This question related to Chapter 7 Science Curiosity Class 6th NCERT.
From the Chapter 7. Temperature and its Measurement.
Give answer according to your understanding.
The thermometer starts cooling, and the liquid contracts.
Explanation: Thermometers must be read while in the liquid to avoid inaccurate readings due to cooling.
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