Download Chapter 5 Ions/Ionic Bonds and Force

Chapter 5
IONS/IONIC COMPOUNDS AND NEWTON’S LAWS (FORCES)
Objectives

Describe force and give examples in nature

Apply newton’s laws to every day examples

State newton’s three laws of force

Identify the four forces found in nature
Types of Forces
There are four forces of nature:

strong nuclear Force

electromagnetic force

weak nuclear force

gravity
Strong nuclear force

The strong nuclear force holds the particles of the nucleus together

strongest of the four forces

always attractive

It only acts over a very short distance, 10-10m (0.000000000010 m)

Ex: the parts of the nucleus, protons and neutrons, are held to
together by nuclear force
Electromagnetic Force

The electromagnetic force is responsible for positive and negative
charges attracting, and like charges repelling

responsible for north poles of magnets attracting south poles, and
like poles repelling

Without the electromagnetic force, negative electrons would not
orbit the positive nucleus

100 times weaker than the strong nuclear force
Weak Nuclear Force

involved in one of the three types of radiation, beta decay
(electrons are emitted eventually changing into a different element)

thousands of times weaker than the strong force

Ex: Actinides release nuclear energy due to the splitting of their
nucleus
Gravity

Gravity causes any mass to be attracted to any other mass

weakest of the four forces

always attractive

Unlike the strong nuclear force, it acts over very large distances
Mass

Mass is the amount of material (matter) in an object

unit of mass is the kilogram (kg)

If you moved an object to the moon, its mass would stay the same
but its weight would change
Inertia

The property of a body to resist changes to its state of motion is
called inertia.

The more inertia an object has, the more difficult it is to speed it up,
slow it down, or change its direction.

(the more mass the more inertia) (less mass, less inertia)
Weight

Weight is equal to mass times the gravitational acceleration of the
object’s location

Earth’s gravitational acceleration = 10m/s2

Weight is a force, measured in Newtons (N)

If an object is moved to another planet or moon with different
gravity, the weight will change
Newton’s First Law of Motion

An object at rest stays at rest and an object in motion stays in
motion with the same speed and in the same direction unless acted
upon by an unbalanced force.

http://www.physicsclassroom.com/mmedia/newtlaws/cci.cfm

http://www.physicsclassroom.com/mmedia/newtlaws/il.cfm
Newton’s Second Law of Motion

MASS RESISTS ACCELERATION:


acceleration of an object depends directly upon the net force acting
upon the object, and inversely upon the mass of the object.
What doe above statement really mean?

As the force acting upon an object is increased, the
acceleration of the object is increased. As the mass of an object
is increased, the acceleration of the object is decreased.
Newton’s Third Law of Motion

For every action, there is an equal and opposite reaction.

All forces result from interactions between objects.

Forces always come in pairs.
Identifying Action and Reaction
Force Pairs

1.
Identify the action – reaction pairs
Action: Baseball pushes glove leftward
Reaction: The glove pushes the baseball rightward
2. Action: Bowling ball pushes pin leftwards.
Reaction: Pin pushes bowling ball rightward
3. Enclosed air particles push balloon wall outwards.
Reaction: Balloon wall pushes enclosed air particles inwards