Download Newton`s three laws of motion are…

Force
Newton’s Laws
Introduction
First Law - Inertia
Second Law – Force and Acceleration
Third Law – Action and Reaction
1
Force
Newton’s Laws
Newton’s three laws of motion are…
Law #1
2
A body at rest will stay at rest unless acted upon by
an external agent and a body in motion will remain
with the same motion, in a straight line, unless
acted upon by an external agent.
Law #2
The force acting on a body is equal to the product of
its mass times its acceleration,
Law #3
Each action has an equal an opposite reaction.


 F  ma
Force
Newton’s Laws
First Law of Motion
Law #1
A body at rest will stay at rest unless acted upon by
an external agent and a body in motion will remain
with the same motion, in a straight line, unless
acted upon by an external agent.
In other words, a change in a particle’s (body’s) speed or
direction can only occur if there is an external force (agent)
acting on it. This can also be seen for each component of the
force.
3
Force
Newton’s Laws
There is something wrong with the way the ball bounces.
Do you know what it is?
Think about the forces that are present and their directions.
Think about Newton’s First Law.
Maybe the next animation will help.
4
Force
Newton’s Laws
Second Law of Motion
Law #2
The force acting on a body is equal to the product of
its mass times its acceleration,


 F  ma
In other words, the sum of the forces acting on a particle is
proportional to its acceleration. The mass is the constant of
proportionality.
5
Force
Newton’s Laws
Third Law of Motion
Law #3
Each action has an equal an opposite reaction.
In other words, for every force acting on a particle, there is
an equal and opposite force that the particle puts on the
object that gave it the original force.
6
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
7
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
8
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
9
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
10
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
11
Force
Newton’s Laws
Name some of the action/reaction pairs in this picture.
12