|
|
|
|
|
|
The light-second is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in onesecond, and is equal to exactly 299792458 metres (just over 186282 miles).
Decimeter or decimetre is equal to 10-1 meter (unit of length), comes from a combination of the metric prefix deci (d) and the SI unit of length meter (m). Plural name is decimeters.