Subscribe to our newsletter. This article discusses the use of significant figures in taking measurements and performing calculations. Learn about significant figures, uncertainty, accuracy, precision, rounding, and truncating. Losing significant figures and effects of exact numbers are also described. These are online conversions for altitude, temperature, pressure, density, and speed of sound.
Many different units are available.
There is an online calculator to find the percent of Carbon 14 remaining after a given number of years and another calculator to find the years that have elapsed based on the percentage of Carbon 14 remaining. Conversion Factors Conversion factors for many, many British, French, and metric units are provided. In addition to the calculator, the site offers FAQs, contact information, mailing lists, table of elements and their atomic mass, and section on known atom groups. There are links to mathematical notation for orders of magnitude, metric prefixes, and common US and metric equivalents. There is also a reference section for geographical locations.