Radians to Streck (rad to streck)
1 radian equals 1,002.676141 streck (rounded).
How to convert radians to streck
To convert radians to streck, multiply the number of radians by 1,002.676141. The factor is rounded to 10 significant digits. To go the other way, multiply streck by 0.0009973310011 (rounded).
streck = radians × 1,002.676141
Example: 10 radians = 10,026.76141 streck.
About these units
Radian (rad)
The SI unit of angle: the angle at the center of a circle subtended by an arc equal in length to the radius. A full turn is 2π radians (about 6.2832).
The radian builds its unit out of the circle itself. Lay a length of string equal to the radius along the circumference, and the angle that arc makes at the center is one radian. The SI Brochure calls it the coherent unit of plane angle, and it also serves as the coherent unit of phase angle, which grows by 2π radians over one period of a repeating wave. The same document notes that you could write rad as m/m, but warns that this is not intrinsic and can mislead, since angle is not the same kind of quantity as an ordinary ratio of lengths. It also records an alternative definition: a right angle equals π/2 radian.
A circle's circumference is 2π times its radius, so a full turn is 2π radians, about 6.2832, which makes one radian roughly 57.3 degrees, or about 0.159 of a turn. The SI Brochure's table of derived units expresses angular velocity in radians per second.
1 radian = 0.1591549431 turns (approximately).
Sources: BIPM SI Brochure, 9th edition (2019); Wikipedia: Angle; NIST Guide to the SI, Appendix B.8 (angle conversion factors)
Streck (Swedish Mil) (streck)
One 6,300th of a full turn, the Swedish military unit. Close to a milliradian (1/6,283).
Swedish gunners divided the circle into 6,300 parts and called each one a streck, which is Swedish for a stroke or line. One streck is therefore 1/6300 of a turn, close to a milliradian, since a true circle holds about 6,283.185 of those. The rounding gave artillery officers a convenient number, because a milliradian covers about one meter at a distance of one thousand meters.
Other armies picked different round numbers. NATO uses 6,400 mils per circle and the Warsaw Pact used 6,000, so mixing the systems in range calculations leads to errors of a few percent. The idea of an angular mil goes back to the Swiss engineer Charles-Marc Dapples in the mid-nineteenth century, and France adopted it for artillery around the First World War.
Sweden later moved to the NATO mil, and before 2007 its defence forces still used the streck, so it is now an obsolete military convention.
1 streck (Swedish mil) = 0.0001587301587 turns (approximately).
Sources: Wikipedia: Milliradian; Wikipedia: Angular mil
Related conversions
- Streck to radians (reverse)
- Radians to degrees
- Radians to gradians
- Radians to turns
- Radians to arcminutes
- Radians to arcseconds
- Radians to milliarcseconds
- Radians to milliradians
- Radians to right angles
- Radians to octants
- Radians to sextants
- Radians to hour angles
- Radians to mils (NATO)
- Degrees to streck
See all angle units.