|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is 299,792,458 metres per second (approximately 3.00×108 m/s, or 186,282 mi/s); it is exact because the unit of length, the metre, is defined from this constant and the international standard for time.
Foot per hour is unit of speed or velocity. It equals 0.00008466 meter per second. Plural name is feet / hour.