Use a piece of wire on the pencil and wind it for 20 turns. As shown in the figure, use a scale to measure the width of 20 turns______ Mm. The diameter of this wire is______ Mm | Math enthusiast | Mathematical art

Use a piece of wire on the pencil and wind it for 20 turns. As shown in the figure, use a scale to measure the width of 20 turns Mm. The diameter of this wire is Mm

It can be seen from the figure that l = 2.00cm = 20.0mm, n = 20, so d = ln = 20.0mm20 = 1.0mm

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