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Question
A tightly closed metal lid of a glass bottle can be opened more easily if it is put in hot water for some time. Explain.
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Solution
When a bottle with a tightly-closed metal lid is put in hot water for sometime, its lid can be opened easily because metals have greater coefficient of expansion than glass. Therefore, when the metal lid comes in contact with hot water, it'll expand more than the glass container. As a result, it will be easier to open the bottle.
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