1. Forces
Forces
and
and
Newton
Newton

2. Newton is famous for discovering
the Force of Gravity, but he also
created 3 important Laws of Motion!

3. Newton’s 1st Law of Motion:
An object in motion will stay in motion,
and an object at rest will stay at rest,
unless acted on by a force.
Translation:
Force is what starts and stops motion!

4. Examples of Newton’s 1st Law:
* a marble will not move unless forced.
* once a marble is moving, it doesn’t
stop until forced to!

5. * if you don’t wear your seatbelt, you
have no force to stop you when
the car crashes!
since you keep moving, you fly through
the windshield! (and DIE)

6. * Things dropped from a moving vehicle don’t fall straight down!
* they keep moving forward until
another force stops them!

7. Special word to explain Newton’s
first law: INERTIA!
Inertia = resistance to change in motion
(things don’t want to start moving
if they are stopped,
or stop moving if they are moving)

8. Newton’s 2nd Law of Motion:
Force = mass X acceleration = x
This means that the magnitude of
the force is decided by how
big and heavy an object is,
and how fast it is moving!

9. This makes sense:
big, heavy objects have a lot of force.
An elephant doesn’t have to move fast!
Small objects can have a lot
of force if they are
moving FAST.
a bullet thrown by hand does nothing,
but shot at high speed it can kill!

10. Newton’s Third Law of Motion:
For every action, there is an equal
and opposite reaction.
Translation: If you push,
you also get pushed back!

11. This is why we are able to jump--
when we push the ground,
it pushes back!