Figure 2 shows a flask filled with water. The flask is fitted with a cork through which a tube is inserted. When the flask is cooled, the water level rises slightly, and then falls steadily.

Figure 2 shows a flask filled with water. The flask is fitted with a cork through which a tube is inserted. When the flask is cooled, the water level rises slightly, and then falls steadily.

Explain this observation.

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when the flask is cooled it contracts and its volume reduces hence the level of water rises slightly. But due to poor conductivity of glass, water falls as its contraction is greater than that of glass

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johnmulu answered the question on April 15, 2017 at 08:54

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