As 'Run 3' begins, CERN touts discovery of exotic particles

The physics lab that's home to the world's largest atom smasher announced on Tuesday the observation of three new "exotic particles" that could provide clues about the force that binds subatomic particles together.

Universal optothermal micro/nanoscale rotors

The fundamental rotation of micro and nano-objects is crucial for the functionality of micro and nanorobotics, as well as three-dimensional imaging and lab-on-a-chip systems. These optical rotation methods can function fuel-free ...

Assigning moving features in high-speed atomic force microscopy

Researchers at Kanazawa University report in Biophysics and Physicobiology how to optimize high-speed atomic force microscopy experiments on live cell membranes, so that moving objects like molecules can be properly followed ...

Methane levels surged in 2020 despite lockdowns

Levels of methane, the second most important greenhouse gas in our atmosphere, continued their unrelenting rise in 2020 despite the economic slowdown caused by the COVID-19 pandemic.

Water receding slowly in flood-hit northeast Bangladesh

Water levels were slowly receding Thursday in major rivers in Bangladesh's flood-hit northeast, bringing hopes of relief to millions of Bangladeshis, but woes continued in India's northeast, where 5.5 million people remained ...

Measuring the bite force of insects

How hard can insects bite? Having a strong chewing apparatus makes it easier to crush harder food and to succeed in fights with enemies. Biologists at the University of Bonn now present a mobile system (forceX) for measuring ...

Video: Why can't I distill liquor at home?

Distilling liquor might be a relatively simple process—heating a fermented liquid and keeping only the boiled alcohol—but it is dangerous and illegal without a license.

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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