How to use common learning stationery to measure the diameter of thin copper wire? (write the use of stationery, measurement method and the expression of the diameter of thin copper wire) Same as above, physical content

How to use common learning stationery to measure the diameter of thin copper wire? (write the use of stationery, measurement method and the expression of the diameter of thin copper wire) Same as above, physical content


The copper wire is wound on the pen for 10 turns, and then measured by a ruler for 10 turns, and then divided by 10