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Long ton

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A long ton is a specific unit used to measure weight. It belongs to the imperial system of measurements. You might also hear it called the imperial ton or the British ton. Some people also call it the displacement ton. It is part of the avoirdupois system of weights. This unit is important for measuring large amounts of materials. It helps people trade goods accurately across different places.

To understand a long ton, you must look at its smaller parts. This unit is built using a sequence of traditional British measurements. First, there is the stone. One stone is equal to 14 pounds. Next, there is the long hundredweight, or cwt. One long hundredweight is equal to 8 stone. Finally, the long ton is made of 20 long hundredweight. When you multiply these parts together, you get exactly 2,240 pounds. This is also equal to 1,016.0 kilograms.

It is very important not to confuse the long ton with the short ton. The short ton is a different unit used in the United States. It is also used in Canada before metrication. A short ton is equal to only 2,000 pounds, or 907.2 kilograms. Because of this difference, a long ton is exactly 12% larger than a short ton. The long ton uses 20 long hundredweight of 112 pounds each. In contrast, the short ton uses 20 short hundredweight of 100 pounds each.

The history of this unit goes back a long time. The long ton was standardized during the 13th century. It has played a major role in international rules and treaties. For example, the Washington Naval Treaty of 1922 used the long ton. This treaty set specific rules for warships. It limited the displacement of battleships to 35,000 long tons. To compare, that is 35,560 tonnes or 39,200 short tons.

In the United States, the long ton still has specific uses. It is commonly used to measure the displacement of ships. Displacement refers to the weight of the water a ship moves. It is also used for shipping bulk commodities. These are large amounts of goods like iron ore or elemental sulfur. These items are often moved in large, heavy piles or bales.

You can visualize the weight of a long ton using salt water. One long ton weighs the same as 35 cubic feet of salt water. This calculation assumes the salt water has a density of 64 pounds per cubic foot. In metric terms, this volume is about 0.991 cubic meters. This density is written as 1.03 grams per cubic centimeter. Using water is a helpful way to picture such a large weight.

Rules for using this unit have changed in the United Kingdom. The United Kingdom passed the Weights and Measures Act of 1985. This was done to comply with the practices of the European Union. Because of this law, the British Imperial ton is excluded from trade. The United Kingdom now uses the tonne for most things. A tonne is a metric unit equal to 1,000 kilograms. However, if people still use the word "ton" there, they usually mean the long ton.

The long ton remains a significant part of global trade systems. It is traditionally used as the unit of weight in international contracts. These contracts involve many different types of bulk goods and commodities. While many places use the metric tonne, the long ton still connects to older systems of measurement. It serves as a bridge between historical British standards and modern global shipping.

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