# Physics Course/Force/Force

## Force

Force is a term used to describe a quantity that acts on an object to change object's state or to perform a task on the object. Example Force used to push or pull a cart or force used to break a stick

## Force's Characteristics

### Force's Pressure

Force exerts on a cross sectional area of a surface of an object is called Pressure

$P = \frac{F}{A}$

### Work Done

The ability of a Force to carry out a task on an object is defined Work done on the object . Work done by a force on an object to move object over a distance s is defined as the product of Force and Distance move

$W = F s = F v t = p v$
$W = F \int v(t) dt$

### Energy

The ability of a Force to carry out a task on an object over a period of Time .

$E = \frac{W}{t} = F \frac{s}{t} = F v = F a t = p a$
$E = \frac{F}{t} \int v(t) dt$

## Types of Force

### Motion Force

Motion Force is a force used to set an object in motion . Force to make an object move is calculated by

$F = m a$
$F = m \frac{v}{t} = \frac{p}{t}$

For any motion of speed v(t) caused by a force

$F = m \frac{dv(t)}{dt}$

### Gravitational Force

Attraction's Force of the Earth to attract any object toward the Earth

$g = G \frac{m}{r^2}$
$F_g = M g = G \frac{m M}{r^2}$

### ElectroMotive Force

ElectroMotive Force is the electric force that set stationary charge to move in a straight horizontal line

$F_E = q E$

### ElectroMagnetoMotive Force

ElectroMagnetoMotive Force is the magnetic force that set the moving charge to move in perpendicular to the horizontal direction

$F_B = \pm vB$

### ElectroMagnetic Force

ElectroMagnetic Force is the sum of the Electric Field Force and the Electric force

$F_EB = F_E + F_B = q(E \pm vB)$

## Summary

Force is used to to describe a quantity that acts on matter to perform a task

1. To cause an object to move or to set an object in motion . Example to push or pull a door
2. To cause matter to change its state . Example change Solid to Liquid to Gas
Force Definition Formula
Motion Force Force causes an object's motion F = m a = $\frac{m v}{t}$ = $\frac{p}{t}$
Gravitation Force Earth's Force to pull an object toward the earth Fg = m g = $G \frac{m M}{R^2}$
Friction Force Force one surface exerts on another surface
Elastic Force Elastic Force of a Spring F = - k x
Electrostatic Force Force of attraction of two stationary Unlike Charge $F_e = K \frac{Q_+ Q_-}{R^2}$
ElectroMotive Force Force causing a stationary charge to move in straigh line $F_E = Q E$
ElectroMagnetoMotive Force Magnetic Force that cause moving charge to move up or down perpendicular to initial direction of travel $F_B = Q v B$
ElectroMagnetic Force The sum of Electrostatic Force and ElectroMagneto Force $F_EB = F_E + F_B = Q (E + vB)$

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