Resistance — may refer to: Physics * Electrical resistance, a measure of the degree to which an object opposes an electric current through it * Friction, the force that opposes (relative) motion ** Drag (physics) ( air resistance ), fluid or gas forces… … Wikipedia
Atkinson resistance — is commonly used in mine ventilation to characterise the resistance to airflow of a duct of irregular size and shape, such as a mine roadway. It has the symbol R and is used in the square law for pressure drop,:Delta P = frac{ ho {actual{ ho… … Wikipedia
Onondaga (geological formation) — The Onondaga Formation is a group of hard limestones and dolostones of Devonian age that form an important geographic feature in the area of outcrop.In upstate New York and southern Ontario the sedimentary rocks tend to slope slightly to the… … Wikipedia
glacial valley — ▪ geological formation also called glacial trough stream valley that has been glaciated, usually to a typical catenary, or U shaped, cross section. U shaped valleys occur in many parts of the world and are characteristic features of mountain… … Universalium
river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… … Universalium
Platinum — This article is about the chemical element. For other uses, see Platinum (disambiguation). iridium ← platinum → gold Pd ↑ Pt ↓ Ds … Wikipedia
Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… … Universalium
Earthquake — For other uses, see Earthquake (disambiguation). Global earthquake epicenters, 1963–1998 … Wikipedia
Titanium — This article is about the chemical element. For other uses, see Titanium (disambiguation). scandium ← titanium → vanadium … Wikipedia
Zirconium — (pronEng|zɚˈkoʊniəm, IPA|/ˌzɝˈkoʊniəm/) is a chemical element with the symbol Zr and atomic number 40. It is a lustrous, gray white, strong transition metal that resembles titanium. Zirconium is used as an alloying agent due to its high… … Wikipedia