Grace Hopper on Letterman
TheLazlo1011 HN recommender · recommended in 1 month, 2016–2018
interview · general · evergreen · 2016–2018 on HN
Grace Hopper appears on Letterman and uses a foot-long piece of wire to show how far light travels in a nanosecond.
Brought up whenever latency, light speed or the size of a nanosecond comes up, as the classic physical demonstration.
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3 comments from Hacker News
No mention of the foot per nanosecond is complete without this seminal scene between the great, late Grace Hopper and David Letterman: ▶ this video
Lightnanoseconds are a useful measure in everyday life as well. A lightnanosecond is about 30cm, or 1 foot. ▶ this video
Latency Math (Almost 100ms faster then current technology) EDIT: This is only one way ALSO Grace Hopper telling David Letterman what a nano second is! ▶ this video 1 Nanosecond = distance light travels one foot 1 mile = 5260 nanoseconds (In a vacuum) Current Satellite Internet = 22,000 miles or 115720000 Nano Seconds = 115.72 ms SpaceX Low Orbit = 715 to 823 Miles 823 miles = 4328980 nano seconds = 4.3 ms