# Marine units of length and speed

To measure at sea the distances between different points and the path traveled by the ship, a value called the nautical mile is adopted.

Nautical mile – the average arc length of one minute of the earth meridian.

The length of the arc of one minute of the earth’s meridian is 1 ‘= 1852.23 – 9.34 cos 2φ, where φ is the latitude of the ship’s elevation in degrees.The nautical mile length adopted in Russia is 1852.00 meters. Approximately 6080 feet.

Why exactly 1852? If we take the shape of the Earth as a ball, then the circumference along the meridian will be 40,000,000 meters.

Hence, 40,000,000 m: 360 ° = 40,000,000: 360 * 60 ‘= 40,000,000: 21,600’ = 1851, 85 meters in 1 ‘.

Example: port distance 48 miles.

Or: 43 miles 8 cables. Or: 43.8 miles.

Kabeltov is one tenth of a nautical mile, rounded off equal to 185 meters. 1 mile = 10 kbt.

Example: the distance to the ship is 14 cables.

Knot – one nautical mile per hour (1.852 km / h) or 0.514 m / s (meters per second).

Example: ship speed 23 knots.

A knot is a linear speed of 1 nautical mile in 1 hour. The term “knot” appeared in the era of sailing, when the speed of the vessel was measured using the so-called sector log – a wooden shield of sector shape, released from the stern of the vessel into the water on the lagoon (braided cable).

Such a sector was held by the processes of the laglin at three points, due to which it maintained a perpendicular position in the water to the direction of travel of the vessel.

Since the sector is inhibited by water, the laglin was etched at approximately the speed of the ship. If the laglin with the help of knots was divided into sections of 50.7 feet, that is, equal to 1 \ 120 miles (6080 \ 50.7 = 120), then at a speed of 1 knot the laglin in 1 minute or in 1 \ 60 hours 1 \ 60 miles (2 knots), and in 0.5 minutes – 1 knot. If, for example, 9 knots were etched in 0.5 minutes, it was believed that the ship was sailing at a speed of 9 knots.

On English maps, feet (0.3048 m) and fathoms of 1.83 m are also used.

The distances traveled by the ship and its speed are determined by the lag.

Example: lag counts miles; lag speed 18 knots; 120 miles in the lag.

Anglo-American system of measures:

1 mile land = 1.6093 km

1 mile English = 1.5240 km

1 mile nautical = 1.8532 km

1 furlong = 201.168 m

1 chain = 20.1168 m

1 floor (leshoz) = 5.4863 m

1 gender, gender, perch = 5.0292 m

1 veil (fathom) = 182.88 cm

1 yard = 91.439 cm

1 ft = 30.479 cm

1 (USA) link = 20.1168 cm

1 inch = 25.399 mm

1 (US) inch = 25,400 mm

1 line = 2.1167 mm

1 point = 0.3528 mm

1 mil = 0.0254 mm

1 palm = 10.16 cm

1 spen = 22.86 cm

1 gallon = 4.5436 L

1 (US) gallon = 3.7853 L

1 quart = 1.1364 L

1 (USA) quart liquid = 0.944 L

1 (USA) quart dry = 1,1012 l

1 pint = 0.5682 L

1 (USA) pint liquid = 0.4731 L

1 (USA) pint dry = 0.5505 L

1 jill = 142.1 ml

1 (USA) jill = 118.3 ml

1 barrel = 163.654 l

1 (USA) barrel = 115.625 L

1 (USA) barrel of oil = 158.75-158.98 l

1 pitch = 9.091 L

1 (USA) pitch = 8,809 l

1 bushel Winchester = 35.236 l

1 koum = 145.4707 l

1 (USA) cum = 140.9532 l

1 quarter = 290.9414 l

1 (USA) quarter = 281.9063 l

1 flipper = 2907.81-2909.414 l

1 oz liquid = 0.02957 l

1 (USA) drachma liquid = 3.6966 l

1 anchor = 45.435 l

1 Fairkin = 40.827 L

1 proof gallon = 2.5944 l

1 (USA) proof gallon for alcohols = 1,890 l

1 thyrsus = 190.930 l

1 hoghead or barrel = 286.39548 l

1 (USA) hoghead or keg = 238.47579 L

1 pipe, butt or barrel = 572.79096 l

1 (USA) pipe, butt or barrel = 476.95158 l

1 (USA) “long” ton = 1016.47 kg

1 (USA) short ton = 907.185 kg

1 centner = 50.802 kg

1 (USA) “long” centner = 50.802 kg

1 (USA) “short” centner = 45.359 kg

1 pound commercial = 453.592 g

1 oz commercial = 28.3495 g

1 drachma commercial = 1.77184 g

1 gran = 0.0648 g

1 quarter = 12.7005 kg

1 moan = 6.3502 kg

1 lb = 373.267 g

1 oz = 31.1034 g

1 (USA) milier (or metric ton) = 1000 kg

1 quintal = 1,588 kg

1 (USA) quintal metric = 100 kg

1 cental = 45.3592 kg

1 doit = 0.13499 mg