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Question
If mercury and glass had equal coefficients of volume expansion, could we make a mercury thermometer in a glass tube?
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Solution
Yes, we can make a mercury thermometer in a glass tube. Mercury and glass have equal coefficients of volume expansion. So, when temperature changes, the increase in the volume of the glass tube as which is equal to the real increase in volume minus the increase in the volume of the container, would be zero. Hence, it will give correct reading at every temperature.
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