Question

why does the knot of a cotton string lasts longer than a that of a silk string

Answer 1

Dear student,

Whenever one talks of tying a knot, the main purpose of creating a knot is to impart or create maximum amount of friction that can be created between the strings. If the friction will be more, the know can be held in the best possible way.The fibre silk is very smooth as compared to the cotton fibre. So when a knot of silk is created, the amount of friction produced between the strings is very large than the friction so created between the silk strings/ So a knot of cotton string will be held very tightly as compared to the silk knot.

Regards