Typical pin - sharp end traces line spirally edge to edge from the start point to opposite side. How long will the line it traces be in mm?
2007-01-03 03:21:02 · 4 answers · asked by a_s_gray 1 in Science & Mathematics ➔ Engineering
depend on how many times around the spiral goes
2007-01-03 04:03:47 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Progress of a spiral is called 'pitch'.
If the pin makes one circuit of the surface, and arrives back at its starting MERIDIAN exactly 1mm from where it last crossed the meridian, then the pitch of the spiral is 1mm.
If the mark made by the pin always crosses the meridian 10mm from where it last crossed, then the pitch will be 10mm.
It is possible to imagine that the pin travels from one pole to the other in exactly one revolution of the sphere. This represents a pitch of 100mm, but it is not the shortest spiral path.
If the pin travels North to South VERY quickly, and the sphere rotates VERY slowly, a spiral path will be drawn that is very nearly a straight line from one pole to the other.
This distance will be VERY NEARLY the same as half of the sphere's 'great circle' (maximum circumference).
The smaller the spiral's pitch, the longer the path will be.
2007-01-03 05:17:07 · answer #2 · answered by Fitology 7 · 0⤊ 0⤋
Absolutely massively long, it really does depend on how fine the line of the pin is....
2007-01-03 03:54:51 · answer #3 · answered by ? 2 · 0⤊ 0⤋
157.35mm
2007-01-03 03:27:24 · answer #4 · answered by Anonymous · 0⤊ 1⤋