Content-Length: 46405 | pFad | https://oceanservice.noaa.gov/education/tutorial_currents/06measure2.html

What is a "knot"? - Currents: NOAA's National Ocean Service Education

U.S. flag An official website of the United States government.

dot gov icon Official websites use .gov

A .gov website belongs to an official government organization in the United States.

https icon Secure websites use HTTPS

A small lock or https:// means you’ve safely connected to a .gov website. Share sensitive information only on official, secure websites.

What is a "knot"?

Currents Tutorial

The term “knot”, in reference to currents, is defined as one nautical mile per hour and is used to measure speed. A nautical mile is slightly more than a standard mile.

1 nautical mile = 1.15 miles = 1.85 kilometers
1 knot = 1.15 miles per hour = 1.85 kilometers per hour
1 knot = 20.251969 inches per second = 51.44 centimeters per second


animation of how knots are measured

The term knot dates from the 17th Century, when sailors measured the speed of their ship by the use of a device called a “common log.”  This device was a coil of rope with uniformly spaced knots tied in it, attached to a piece of wood shaped like a slice of pie.  The piece of wood was lowered from the back of the ship and allowed to float behind it. The line was allowed to pay out freely from the coil as the piece of wood fell behind the ship for a specific amount of time.  When the specified time had passed, the line was pulled in and the number of knots on the rope between the ship and the wood were counted.  The speed of the ship was said to be the number of knots counted (Bowditch, 1984).









ApplySandwichStrip

pFad - (p)hone/(F)rame/(a)nonymizer/(d)eclutterfier!      Saves Data!


--- a PPN by Garber Painting Akron. With Image Size Reduction included!

Fetched URL: https://oceanservice.noaa.gov/education/tutorial_currents/06measure2.html

Alternative Proxies:

Alternative Proxy

pFad Proxy

pFad v3 Proxy

pFad v4 Proxy