In physics, a force is any influence that causes an object to undergo a certain change, either concerning its movement, direction, or geometrical construction. It is measured with the SI unit of newtons and represented by the symbol F. 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.
The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional the mass of the object. As a formula, this is expressed as:
where the arrows imply a vector quantity possessing both magnitude and direction.
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.
Read more about Force: Development of The Concept, Pre-Newtonian Concepts, Newtonian Mechanics, Descriptions, Fundamental Models, Non-fundamental Forces, Rotations and Torque, Kinematic Integrals, Potential Energy, Units of Measurement
Other articles related to "force":
... featuring the words Royal Australian Air Force, beneath which scroll work displays the Latin motto (shared with the Royal Air Force) Per Ardua Ad Astra ...
... A fluid flowing past the surface of a body exerts surface force on it ... Lift is the component of this force that is perpendicular to the oncoming flow direction ... It contrasts with the drag force, which is the component of the surface force parallel to the flow direction ...
... in the mid-latitudes with air being deflected by the Coriolis force to create the prevailing westerly winds ... the large scale interaction of pressure gradient force and deflecting force that in the end causes air masses to move along isobars was understood ... By 1912, this deflecting force was named the Coriolis effect ...
... The SI unit of force is the newton (symbol N), which is the force required to accelerate a one kilogram mass at a rate of one meter per second squared, or kg·m·s−2 ... The gravitational foot-pound-second English unit of force is the pound-force (lbf), defined as the force exerted by gravity on a pound-mass in the standard gravitational field of 9.806 ... The pound-force provides an alternative unit of mass one slug is the mass that will accelerate by one foot per second squared when acted on by one pound-force ...
... The life force was a combined clock and progress meter used to track the energy status of the dungeoneer (the main contestant) ... taking too long (Treguard would often tell the team "You're wasting Life Force"), taking "damage" through being attacked by monsters or obstacles, taking the wrong route or making bad ... In the first five series, the life force was a computer animated image of an adventurer wearing a helmet ...
Famous quotes containing the word force:
“This is the true joy in life, the being used for a purpose recognized by yourself as a mighty one; the being thoroughly worn out before you are thrown on the scrap heap; the being a force of Nature instead of a feverish selfish little clod of ailments and grievances complaining that the world will not devote itself to making you happy. And also the only real tragedy in life is being used by personally minded men for purposes which you recognize to be base.”
—George Bernard Shaw (18561950)
“The connections between and among women are the most feared, the most problematic, and the most potentially transforming force on the planet.”
—Adrienne Rich (b. 1929)
“The affirmative class monopolize the homage of mankind. They originate and execute all the great feats. What a force was coiled up in the skull of Napoleon!”
—Ralph Waldo Emerson (18031882)