Clockwise and counterclockwise
A
clockwise motion is one that proceeds 'like the
clock's hands': from the top to the right, then down and then to the left, and back to the top. The opposite sense of rotation is
counterclockwise (occasionally known as
widdershins or
withershins).
Technically, the terms clockwise and counterclockwise can only be applied to a rotational motion once a side of the rotational plane is specified, from which the rotation is observed. For example, the daily rotation of the Earth is counterclockwise when viewed from the North Pole, and clockwise when viewed from the South Pole.
Clocks traditionally follow this sense of rotation because of the clock's predecessor: the sundial. Clocks were first built in the North Hemisphere, and they were made to work like sundials. In order for the sundial to work (in the North), it must be placed looking Southward. Then, when the Sun moves in the sky (East to South to West), the shadow cast by the sundial moves in the opposite direction, that is West to North to East. That's why hours were drawn in sundials in that manner, and that's why modern clocks have their numbers set in the same way.
Occasionally, clocks whose hands revolve counterclockwise are nowadays sold as a novelty.
Typically, screws and bolts are loosened counterclockwise and tightened clockwise. One mnemonic for remembering this is "righty-tighty, lefty-loosey" (right to tighten, left to loosen.)
In trigonometry, an angle in standard position is measured counterclockwise from the positive x-axis.
In the News
Yale Scientists Identify Structure For RNA Quality Control
A report by Yale scientists in the journal Cell sheds new light on how the protein Ro, a major autoantigen in patients with autoimmune disease, recognizes misfolded RNAs, creating a RNA quality control system for cells. FDA's New Drug Safety Initiative
In 2005 the FDA proposed creating the Drug Watch Web Page, a new program that would communicate "the most up-to-date information possible on emerging [drug] safety issues to the public, even before FDA ... decides whether a regulatory action is appropriate."Includes guidance from the FDA, drug specific information for health professionals and consumers, and related information. From the U.S. Food and Drug Administration (FDA), Center for Drug Evaluation and Research (CDER). Mennonite Weekly Review
Online edition of this "inter-Mennonite newspaper published weekly since 1923."It provides news coverage and editorials from an Anabaptist/Mennonite viewpoint. Some of the topics covered include ecumenical gatherings, the Mennonite Church's work in other countries, and the 2006 Amish school shootings at the West Nickel Mines Amish School in Pennsylvania. Archives go back to 2001. Includes related links. Brain Area That Helps To Suppress Unconscious Actions Discovered
The brain's so-called 'supplementary motor regions', located in the medial frontal cortex, play a key role in suppressing unconsciously-triggered actions which occur when we encounter familiar objects and situations, according to new research. Researchers Unravel A Mystery About DNA
UCLA researchers in collaboration with researchers at Rutgers University have solved longstanding mysteries surrounding DNA transcription, the first step in carrying out instructions contained in our genes. The Blind Fragging the Blind
If you need to improve your hand-to-ear coordination, you can take advantage of a growing library of computer games for the blind, including audio versions of Quake and Doom. By David Cohn. Black Holes In A Radar Trap
European astronomers succeeded for the first time to confirm the signatures predicted near Black Holes by Albert Einstein's theory of Relativity in the light of the cosmic X-ray background. The group of scientists led by Günther Hasinger, director at the Max-Planck-Institute for extraterrestrial Physics in Garching near Munich could identify the spectral fingerprint of iron atoms. Radiohead, The Verve, Other Bands Seek Piece of Ticket Scalpers' Actio
Thriving online markets make it easier than ever for ticket resellers to squeeze premium pricing out of eager would-be concert-goers. Now bands and their managers want a cut. Scientists Identify A Septic Shock Susceptibility Gene
In the November 15th issue of Genes &Development, Dr. Robert Schneider and colleagues at NYU School of Medicine report that the AUF1 gene underlies susceptibility to septic shock. New Pathway Identified In Angiogenesis
Scientists have discovered a new biological pathway that may be useful in regulating angiogenesis, the process the body uses to build new blood vessels. The findings, published in the December issue of the journal Immunity, may offer clinicians a new way to intervene in a broad range of diseases and disorders, including cancer, heart and lung disease, wound healing and transplantation.
MP3 Music Downloads
Preview songs, Download Free Music,Burn CDs at ITunes.com
 
|
