What is a force?

Inphysics, aforceis any interaction that, when unopposed, will change themotionof anobject.

[1]In other words, a force can cause an object withmassto change itsvelocity(which includes to begin moving from astate of rest), i.

E. , toaccelerate.

Force can also be described intuitively as a push or a pull.

A force has bothmagnitudeanddirection, making it avectorquantity.

It is measured in theSI unitofnewtonsand represented by the symbolF.

The original form ofNewton's second lawstates that the net force acting upon an object is equal to therateat which itsmomentumchanges with time.

If the mass of the object is constant, this law implies that theaccelerationof 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 to themassof the objectRelated concepts to force include : thrust, which increases the velocity of an object ; drag, which decreases the velocity of an object ; andtorque, which produceschanges in rotational speedof an object.

In an extended body, each part usually applies forces on the adjacent parts ; the distribution of such forces through the body is the so - called internalmechanical stress.

Such internal mechanical stresses cause no accelation of that body as the forces balance one another.

Pressure, the distribution of many small forces applied over an area of a body, is a simple type of stress that if unbalanced can cause the body to accelerate.

Stress usually causesdeformationof solid materials, or flow influids.