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While sewing, a person often wets the en...

While sewing, a person often wets the end of a thread before, trying to put it through the eye of the needle. Why?

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On wetting the end of a thread, a thin film of water is formed over its fibres. Due to surface tension of the water, the fibres of the thread cling together. As a result, the area of cross section of the thread decreases and it becomes easier to put it through the eye of a needle.
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