Addiction

Little evidence interventions prevent illicit drug use in youth

The U.S. Preventive Services Task Force (USPSTF) concludes that current evidence is inadequate for assessing the balance of benefits and harms of primary care interventions for preventing illicit drug use among children, ...

Diseases, Conditions, Syndromes

Virus cases drop to zero in China but surge in Latin America

New coronavirus cases dropped to zero in China for the first time Saturday but overwhelmed hospitals across Latin America – both in countries lax about lockdowns and those lauded for firm, early confinement. The virus hit ...

Neuroscience

Mind-controlled arm prostheses that can 'feel'

For the first time, people with arm amputations can experience sensations of touch in a mind-controlled arm prosthesis that they use in everyday life. A study in the New England Journal of Medicine reports on three Swedish ...

Health

USPSTF: Behavioral interventions likely prevent tobacco use

(HealthDay)—The U.S. Preventive Services Task Force (USPSTF) concludes that primary care-feasible behavioral interventions have a moderate net benefit for preventing tobacco use in children. These findings form the basis ...

Diseases, Conditions, Syndromes

Canada launches serological testing initiative to manage COVID-19

The Government of Canada is launching a task force to measure the scope of coronavirus infection in Canada and rapidly provide information needed to manage the COVID-19 pandemic and safely get Canadians back to work.

Medical research

Sensor detects biomarker of early-stage multiple sclerosis

Researchers at the Federal University of São Carlos (UFSCar) in Sorocaba (state of São Paulo, Brazil) have developed a technique to diagnose early-stage multiple sclerosis, a disease of the central nervous system, and distinguish ...

Diseases, Conditions, Syndromes

Singapore reports record jump in virus infections

Singapore late Thursday reported a record jump in coronavirus cases, most of them linked to packed dormitories housing foreign workers, as it battled a second wave of infections.

Psychology & Psychiatry

Support plan boosts confidence of military spouses

A support programme that aims to boost retention in the Armed Forces has received a positive research evaluation from Anglia Ruskin University (ARU), with military personnel reporting increased confidence in their employment ...

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Force

In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate, or which can cause a flexible object to deform. Force can also be described by intuitive concepts such as a push or pull. A force has both magnitude and direction, making it a vector quantity. Newton's second law, F=ma, was originally formulated in slightly different, but equivalent terms: the original version states that the net force acting upon an object is equal to the rate at which its momentum changes.

Related concepts to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque which produces changes in rotational speed of an object. Forces which do not act uniformly on all parts of a body will also cause mechanical stresses, a technical term for influences which cause deformation of matter. While mechanical stress can remain embedded in a solid object, gradually deforming it, mechanical stress in a fluid determines changes in its pressure and volume.

This text uses material from Wikipedia, licensed under CC BY-SA