Extra Material: The Equations Behind the Words
It is usually more convenient to use metric units (technically the International System of Units or SI). A brief list of some of the more useful units is given in Table 13.1. A meter is about a yard long and a raisin weighs about a gram. Water boils at 373 K, room temperature is about 293 K, water freezes at 273 K, and the remnants of the Big Bang explosion are now at about 3 K. Nothing can be colder than absolute zero, which is 0 K. One of the advantages of using SI is that when going from large to small (or vice versa) it is easier to change to a more convenient unit, since larger units are just multiples of 10 times the basic unit, see Table 13.2. For example 1 km is 1000 m and 1 m is 100 cm, so a kilometer is 100,000 cm and a kilogram is 100,000 cg. Now, quickly, a mile is how many inches?