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Grace Hopper on Letterman

TheLazlo101 · 447.5K views · 2012-12-12 · 10:00

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Overview

Grace Hopper appears on Letterman and uses a foot-long piece of wire to show how far light travels in a nanosecond.

On Hacker News

Brought up whenever latency, light speed or the size of a nanosecond comes up, as the classic physical demonstration.

Recommended by 1 HN people across 1 months · HN mentions 2016–2018

Topics

History of computingTech pioneers & interviewsFundamental physics
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grace hoppernanosecondlettermanlatencycomputing history

What people said

bouvin · 2017-12 · Recommendation

No mention of the foot per nanosecond is complete without this seminal scene between the great, late Grace Hopper and David Letterman: [VIDEO]

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adrianN · 2018-07 · Reference

Lightnanoseconds are a useful measure in everyday life as well. A lightnanosecond is about 30cm, or 1 foot. [VIDEO]

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baldfat · 2016-11 · Reference

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! [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

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Sources

Video by TheLazlo101, played through YouTube.

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