# Force

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Force is the push or pull of an object resulting in a change from rest or motion.  So when you apply force to an object the velocity changes, the change in velocity is acceleration.  Force is a vector quantity having magnitude and direction, some of these include acceleration, displacement, drag, lift, momentum, thrust, torque, velocity, and weight.

### Contact Forces

• Frictional force
• Tensional force
• Normal force
• Air Resistance force
• Applied force
• Spring force

### Action at a distance Forces

• Gravitational force
• Electrical force
• Magnetic force

### Force Formula

 Equation 1: $$\large{ F = ma }$$ Equation 2: $$\large{ F = p A }$$         Where: $$\large{ F }$$ = force $$\large{ m }$$ = mass $$\large{ a }$$ = acceleration $$\large{ A }$$ = area $$\large{ p }$$ = pressure

## Applied Force

Applied force ( $$F_a$$ ) can come from different types of forces, one of them could be Newton's Second Law.  There really is no single formula.

## Centrifugal Force

Centrifugal force is when a force pushes away from the center of a circle, but this does not really exist.  When an object travels in a circle, the object always wants to go straight, but the centripetal force keeps the object traveling along an axis of rotation.

## Concurrent Force

All of the forces act at the same point.

## General Three-dimensional Force

All other combinations of nonconcurrent, nonparallel and noncoplanar forces.

## Parallel Force

All the forces are parallel (not necessarily in the same direction)

Tags: Equations for Force