Knots to Light Speed
Converter

Conversion Table

How to convert

1 knot (kt) = 1.716E-09 light speed (ls). Knot (kt) is a unit of Speed used in Standard system. Light Speed (ls) is a unit of Speed used in Metric system.

Knots

Definition of Knots

Knots, commonly denoted kn, is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h (approximately 1.151 mph or 0.514 m/s). It is the standard unit of speed used in meteorology, and in maritime and air navigation. A vessel travelling at 1 kn along a meridian travels approximately one minute of geographic latitude in one hour.

How to Convert Knots

To convert knots to other units of speed, we need to multiply or divide by the corresponding conversion factors. For example, to convert knots to kilometers per hour, we need to multiply by 1.852, since there are 1.852 kilometers in one nautical mile. To convert knots to meters per second, we need to divide by 3.6, since there are 3.6 seconds in one hour.

Here are some examples of how to convert knots to other units of length in the US Standard system and the SI system:

• To convert 10 kn to kilometers per hour (km/h), we multiply by 1.852: 10 kn x 1.852 = 18.52 km/h
• To convert 20 kn to miles per hour (mph), we multiply by 1.1507794480235, since there are 1.1507794480235 miles in one nautical mile: 20 kn x 1.1507794480235 = 23.01558896047 mph
• To convert 30 kn to feet per second (fps), we multiply by 1.6878098571012, since there are 1.6878098571012 feet in one meter: 30 kn x 1.6878098571012 = 50.634295713036 fps
• To convert 40 kn to meters per second (m/s), we divide by 3.6: 40 kn / 3.6 = 11.111111111111 m/s
• To convert 50 kn to meters per minute (m/min), we multiply by 60, since there are 60 minutes in one hour: 50 kn x 60 = 3,000 m/min
• To convert 60 kn to centimeters per second (cm/s), we multiply by 100, since there are 100 centimeters in one meter, and divide by 3.6: 60 kn x 100 / 3.6 = 5,000 cm/s

Where Knots Are Used

Knots are used in various fields of science and technology where the speed and direction of movement of objects or phenomena are measured or applied in relation to water or air currents. For example:

• In meteorology, knots are used to measure wind speed and direction, as well as the speed and direction of storms, hurricanes, and other weather phenomena.
• In maritime navigation, knots are used to measure the speed and direction of ships, boats, submarines, and other watercraft, as well as the speed and direction of ocean currents, tides, and waves.
• In air navigation, knots are used to measure the speed and direction of aircraft, helicopters, rockets, satellites, and other aerospace vehicles, as well as the speed and direction of air currents, jet streams, and wind shear.

History of Knots

The origin of knots as a unit of speed can be traced back to the ancient practice of measuring the speed of ships by using a device called a chip log or log-line. This device consisted of a wooden board attached to a rope with knots tied at regular intervals along its length. The board was thrown overboard from the stern of the ship and allowed to drag behind it while the rope was let out for a fixed amount of time (usually measured by a sandglass). The number of knots that passed over the rail of the ship during that time indicated the speed of the ship in nautical miles per hour.

The first recorded use of this method was by the Phoenicians around the second millennium BCE. The device was later improved and standardized by various civilizations such as the Greeks, Romans, Arabs, Vikings, Chinese, and Europeans. The length of the nautical mile and the spacing of the knots varied from place to place and from time to time until they were fixed by international agreement in the late nineteenth century.

The term knot was derived from the Old English word cnotta meaning “a knot”. It was first used as a unit of speed by English sailors in the early seventeenth century.

Example Conversions of Knots to Other Units

Here are some examples of how to convert knots to other units of speed, using the conversion factors given above:

• To convert 100 kn to kilometers per hour, we multiply by 1.852: 100 kn x 1.852 = 185.2 km/h
• To convert 200 kn to miles per hour, we multiply by 1.1507794480235: 200 kn x 1.1507794480235 = 230.15589792094 mph
• To convert 300 kn to feet per second, we multiply by 1.6878098571012: 300 kn x 1.6878098571012 = 506.34295713011 fps
• To convert 400 kn to meters per second, we divide by 3.6: 400 kn / 3.6 = 111.11111111111 m/s
• To convert 500 kn to meters per minute, we multiply by 60: 500 kn x 60 = 30,000 m/min
• To convert 600 kn to centimeters per second, we multiply by 100 and divide by 3.6: 600 kn x 100 / 3.6 = 50,000 cm/s
• To convert 700 kn to millimeters per minute, we multiply by 1000, since there are 1000 millimeters in one meter, and multiply by 60: 700 kn x 1000 x 60 = 42,000,000 mm/min

Light Speed

Definition of Light Speed

Light speed, commonly denoted c, is a universal physical constant that is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour). It is the speed at which light waves propagate through vacuum, and also the upper limit for the speed at which any form of matter or energy can travel through space. Light speed is an essential parameter in the theories of relativity and electromagnetism, and has relevance beyond the context of light and electromagnetic waves.

How to Convert Light Speed

To convert light speed to other units of speed, we need to multiply or divide by the corresponding conversion factors. For example, to convert light speed to kilometers per hour, we need to multiply by 3,600, since there are 3,600 seconds in one hour. To convert light speed to miles per hour, we need to multiply by 2.2369362920544, since there are 2.2369362920544 miles in one kilometer.

Here are some examples of how to convert light speed to other units of length in the US Standard system and the SI system:

• To convert c to kilometers per hour (km/h), we multiply by 3,600: c x 3,600 = 1,079,252,848.8 km/h
• To convert c to miles per hour (mph), we multiply by 2.2369362920544: c x 2.2369362920544 = 670,616,629.384 mph
• To convert c to feet per second (fps), we multiply by 3.2808398950131, since there are 3.2808398950131 feet in one meter: c x 3.2808398950131 = 983,571,056.43 fps
• To convert c to knots (kn), we multiply by 1.9438444924406, since there are 1.9438444924406 nautical miles in one kilometer: c x 1.9438444924406 = 582,749,918.284 kn
• To convert c to meters per second (m/s), we use the exact value: c = 299,792,458 m/s
• To convert c to meters per minute (m/min), we multiply by 60, since there are 60 seconds in one minute: c x 60 = 17,987,547,480 m/min

Where Light Speed Is Used

Light speed is used in various fields of science and technology where the properties and behavior of light and electromagnetic waves are studied or applied. For example:

• In astronomy and cosmology, light speed is used to measure astronomical distances and time scales, such as light-years and parsecs. It also determines the observable size and age of the universe and the effects of gravity on light such as gravitational lensing and gravitational redshift.
• In physics and engineering, light speed is used to calculate the energy and momentum of particles and fields using the famous equation E = mc2. It also sets the limit for causality and information transfer in physical systems.
• In communication and navigation, light speed is used to determine the delay and bandwidth of signals transmitted through various media such as optical fibers or radio waves. It also affects the accuracy and precision of measurements based on time-of-flight or Doppler effect methods.

History of Light Speed

The concept of light speed has a long history that spans across different cultures and disciplines. Some of the milestones in its development are:

• In ancient times, many philosophers and scientists assumed that light traveled instantaneously or infinitely fast.
• In the late 17th century, Danish astronomer Ole Romer was the first to demonstrate that light had a finite speed by observing the apparent motion of Jupiter’s moon Io. He estimated that light took about 22 minutes to cross the diameter of Earth’s orbit.
• In the early 18th century, English astronomer James Bradley discovered the aberration of starlight caused by Earth’s motion around the Sun. He used this phenomenon to calculate that light traveled about 10 thousand times faster than Earth’s orbital speed.
• In the late 19th century, French physicist Hippolyte Fizeau and American physicist Albert Michelson conducted various experiments using rotating mirrors or interferometers to measure the speed of light more accurately in air or vacuum.
• In the early 20th century, German-born physicist Albert Einstein proposed the special theory of relativity, which postulated that light speed was constant and independent of the motion of the source or the observer. He also showed that light speed was the maximum speed for any form of matter or energy in the universe.
• In the late 20th century, various methods and standards were developed to define and measure light speed more precisely and consistently. In 1983, the International System of Units (SI) adopted the exact value of 299,792,458 metres per second as the definition of light speed in vacuum.

Example Conversions of Light Speed to Other Units

Here are some examples of how to convert light speed to other units of speed, using the conversion factors given above:

• To convert c to kilometers per hour, we multiply by 3,600: c x 3,600 = 1,079,252,848.8 km/h
• To convert c to miles per hour, we multiply by 2.2369362920544: c x 2.2369362920544 = 670,616,629.384 mph
• To convert c to feet per second, we multiply by 3.2808398950131: c x 3.2808398950131 = 983,571,056.43 fps
• To convert c to knots, we multiply by 1.9438444924406: c x 1.9438444924406 = 582,749,918.284 kn
• To convert c to meters per second, we use the exact value: c = 299,792,458 m/s
• To convert c to meters per minute, we multiply by 60: c x 60 = 17,987,547,480 m/min
• To convert c to centimeters per second, we multiply by 100: c x 100 = 29,979,245,800 cm/s