Metric and Imperial equivalents

This article is a travel topic Most countries in the world now use the metric system. Almost the only holdouts are the USA and the United Kingdom which, oddly enough, still use the old British Imperial system of weights and measures. The only units the two systems have in common are time units from second to century. We use "=" signs below, but all are approximate. Temperature ←freezing cold cool mild warm hot swelter cooked→ °C  -4 0 4 7 10 13 15 18 21 24 26 30 32 35 40 °F  25 32 40 45 50 55 60 65 70 75 80 85 90 95 104   100 °C — 212 °F — water boils 37 °C — 98.6 °F — human body temperature 0 °C — 32 °F — water freezes -18 °C — 0 °F — ouch -40 °C — -40 °F — forty below zero! Humidity. Hot weather, say 80°F (26°C) and up, is more uncomfortable in humid air than in dry air because dry air allows more sweat to evaporate from your skin and this cools you but humid air inhibits this evaporation and leaves you more susceptible to overheating. For those who are not used to Metric thermometers, there are a few ways to think about it... Option 1: From Metric (Celsius) to Fahrenheit, double the number and add 30. From Fahrenheit to Celsius, subtract 30 and divide in half. This is not exact and it won't work for much higher or lower temps, but it will be close enough to understand what the temperature is. Option 2: A nice little poem to remember for Celsius... Zero is freezing 10 is not 20 is warm and 30 is hot Option 3: For the mathematically inclined: Fahrenheit=(C*1.8)+32. Celsius=(F-32)/1.8 Length and distance 1 inch (1") = 2.54 cm 1 foot (1') = 30 cm 1 mile = 1.6 km Comparisons A credit card is about 0.75 mm (3/4 of a millimetre) thick. 1 cm (centimetre) is the width of an average fingernail. Most adults are between 1.5 and 2 metres tall. 1 km (Kilometre) takes about 15 minutes to walk. Weight 1 kg = 2.2 pounds 1 ounce = 28.54 grams 1 pound = 454 grams For China, the jing is almost exactly 500 grams. Surface area For small things, one might use square inches or square centimeters. There are about 6.5 cm2 to one in2. For floor area of an apartment, there are about 11 square feet to the square meter. For large areas, there are about 2.5 acres to the hectare. Volume The standard metric unit of volume is the litre. Many things, however, are measured in ml (millilitres) or equivalently in cc (cubic centimetres). Roughly, a teaspoon is 5 cc and a fluid ounce is 30 cc. In both the US and Imperial systems, 4 quarts = 1 gallon and 2 pints = 1 quart. However, the US units are smaller than Imperial counterparts. A US quart is 32 fuid ounces while Imperial is 40; a liter is in between at 35. A US gallon is 128 ounces or 3.78 litres, while an Imperial gallon is 160 ounces or 4.54 litres. For car and motorcycle engines, displacement might be given in cc or litres or cubic inches. 1000 cc or one litre is 61 cubic inches. Comparisons 1 L of water weighs 1 kg. Since many liquids (milk, orange juice) are sold in litre containers it is easy to judge 1 L or 1 kg. 1 L is equivalent to a cube 10 cm x 10 cm x 10 cm. 1 Cubic m (1 m3) = 1000 litres. 1 m3 of water weighs 1000 kg = 1 Tonne. Do not try to pick this up yourself! In Europe, wine is usually sold in 700 mL (0.7 L) bottles (occasionally 750 mL or 1 L). Metric prefixes 1 mm = 1 / 1000 metres, 1 mg = 1 / 1000 g, 1 mL = 1 / 1000 Litres. 1 cm = 1 / 100 metres. 1 km = 1000 metres, 1 kg = 1000 grammes.