MoEDAL hunts for dyons

A magnetic monopole is a theoretical particle with a magnetic charge. Give it an electric charge, and you get another theoretical beast, dubbed a dyon. Many "grand unified theories" of particle physics, which connect fundamental ...

Galaxy formation simulated without dark matter

For the first time, researchers from the Universities of Bonn and Strasbourg have simulated the formation of galaxies in a universe without dark matter. To replicate this process on the computer, they have instead modified ...

How do woodpeckers avoid brain injury?

Slamming a beak against the trunk of a tree would seem like an activity that would cause headaches, jaw aches and serious neck and brain injuries. Yet woodpeckers can do this 20 times per second and suffer no ill effects.

Stress test reveals graphene won't crack under pressure

Graphene is a paradox. It is the thinnest material known to science, yet also one of the strongest. Now, research from University of Toronto Engineering shows that graphene is also highly resistant to fatigue—able to withstand ...

page 1 from 23

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