Force and Motion - Newton's Laws (Form 4 Chapter 2 Physics)

 

Experiment - Inertia

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Inertia

Inertia – natural characteristics of an object to oppose any attempted change on its original state, whether at rest or in motion – tendency of an object to remain at rest, or to keep moving at constant speed in a straight line

Newton’s First Law of Motion (Law of Inertia) 

Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.

Force

Force is the product of mass and acceleration.
Force changes the size, shape, state of rest, velocity and/or direction of an object.
Force is a vector quantity.

Newton’s Second Law of Motion

The acceleration of a body, a, is directly proportional to the net force acting upon it, F, and
inversely proportional to its mass, m.

where F = force in [N]
m = mass in  [kg]
a = acceleration caused by F in [m/s^2]

Forces in Equilibrium: 

Equilibrium:
- resultant force = 0
- acceleration = 0 (stationary or uniform velocity)

Newton’s Third Law 

For every action there is an equal and opposite reaction.