Forces and motion were discussed. A force is a push or pull that can cause changes in an object's motion by affecting its position, direction, speed, or acceleration. Newton's three laws of motion state that an object at rest stays at rest and an object in motion stays in motion unless acted on by an unbalanced force, acceleration depends on mass and applied force, and for every action there is an equal and opposite reaction. Simple machines like levers, pulleys, and inclined planes make work easier by trading force for distance.

2. E s s e n t i a l
Q u e s t i o n s :
Wh a t i s a
• When you jump up in c e ?
f o r the air, what pulls you back
down W Earth? t
to h a e f f e c t
• What pulls e magnet together oro r c it e
d o a s a f pushes apart?
• The answer is….
h a v e o n a n
o b j e c t ?

3. A FORCE is a push or pull that causes
a change in motion.
• Nothing can change position, speed, or direction unless a
force acts on it.
• A book doesn’t just fall off of a table by itself. A force has to
push it!
Forces can affect motion in several ways:
→ They can make objects start moving
→ They can make objects move faster
→ They can make objects move slower
→ They can make objects stop moving
→ They can make objects change direction

4. Essential Questions: What happens when two
unequal forces push an object in the same direction?
What happens when two unequal forces push and
object in opposite directions?

5. E s s e n t i a l
Q u e s t i o n s :
Wh a t a r e s o m e
•Friction- ise force that works against motion e s
t y p a s o f f o r c
• can makefthingsi slow down or o n or it
( r c t i stop, ,
can keep things from moving at all
• greater between a v surfaces than between
g r rough i t y ,
msmooth one e t i c
a g n f o r c e )
•Ice skaters glide along? ice because there is
the
little friction between the blades and the ice.

8. E s s e n t i a l
Q u e s t i o n s :
Wh a t a r e s o m e
t y p e s o f f o r c e s
Gravity f r i c t ie o n ,
( i s t h
u n i g r a v ia t y ,
v e r s l
m aa t g t n r e at c i t c i o f n o r c e )
b e t w e e n? a n y t w o
o b j e c t s w i t h
m a s s .

9. E s s e n t i a l
Q u e s t i o n s : Wh a t
a r e s o m e t y p e s
o f f o r c e s
Magnetic ( f r i c that i o n iron is
Force- anything t attracts ,
considered g r a That’s why y , clips are
magnetic. v i t paper
attracted to a magnet. Paper clips contain iron. The
m a g called the magnetic force.
force of a magnet is
n e t i c
A magnet is afpiece of metal that pulls? attracts
o r c e ) or
things which have iron or steel in them. The most
common magnets are in the shape of a bar or
horseshoe. The magnet is surrounded by a force
field which attracts iron, especially at the poles.

10. M a g n e t s
a r e
s u r r o u n d
e d b y a
f o r c e
f i e l d
w h i c h
a t t r a c t s
i r o n ,
e s p e c i a l
l y a t
t h e

11. Let’s Review
Which of the following is an example of trying to
increase the friction?
A. Squirting oil in hinges
B. Spreading grit on icy roads
C. Waxing the underneath of skis

12. Mr. Gates mops the gymnasium floor every day.
When he finishes mopping, he puts up the sign
shown below. The effect of which force is weakened
when the floor is wet?
A. friction
B. gravitation
C. inertia
D. magnetism

13. Let’s Review
N S S N
What is happening between these two magnets?
• A.) The magnets pull toward each other because like poles
attract.
• B.) The magnets push away from each other because like poles
attract.
• C.) The magnets pull toward each other because like poles
repel.
• D.) The magnets push away from each other because like poles
repel.

14. Let’s Review
On which surface will a toy car travel the farthest?
A. Ice
B. Wood
C. Carpet

15. Let’s Review
Which of the following is NOT a type of force?
A. magnetic
B. friction
C. motion
D. gravity

17. Characteristics of
Motion
• The motion of an object can be described by its:
• Position
• Direction
• Speed
• Velocity
• Position, direction, speed, & velocity can be changed by
forces that act on the object.

18. Position
• Position is the location of an object
2 feet
• The dog is 2 feet away from the tree. This picture shows the
position of each object: the dog and the tree.

19. Direction
• Motion can also be described using
directions such as north, south, east, &
west. Direction of an object depends on the
direction of the force. It can be measured
with a compass.
• The bird flew up, the car turned left, the
rabbit ran toward the gate, the dog ran away
from the house
• Objects can also move toward and away.

20. Speed
• Position and direction are helpful in describing motion.
Yet motion also occurs over time.
• For example- You threw a football 20 meters. But did
the football go 20 meters in 2 minutes? 2 seconds?
• Speed is the measurement of distance over time.
• You can use a stopwatch to measure speed

21. Velocity
• Velocity is the object’s speed BUT includes direction
• Remember, DIRECTION includes north, south, east and
west- following the points of a compass.
• For example- the football that was thrown 20 meters in
2 seconds is traveling 10 meters per second (20/2 =
10). You MUST include direction for velocity. So your
answer might really be 10 meters per second west!
States the direction
the ball traveled

22. Measuring Motion
• Scientists use many tools to measure
motion:
• Commonly used to measure direction is
the compass.
• A meterstick is commonly used to
measure distance between one position
and another.
• A stopwatch is used to measure time

23. Let’s Review
• Which of the following is the BEST
description of the position of the
eraser?
• A.) The eraser is near the
pencil
• B.) The eraser is to the left of
the pencil
4 cm
• C.) The eraser is 4 cm away
from the pencil
• D.) The eraser is 4 cm to the
left of the pencil

24. Let’s Review
• What is the speed of a hockey puck that
moves 45 meters in 5 seconds?
• A.) 45 meters per second
• B.) 17 meters per second
• C.) 9 meters per second
• D.) 5 meters per second

25. Let’s Review
• What is velocity?
• A.) speed and position
• B.) speed and direction
• C.) position and direction
• D.) direction and time

27. Newton’s First Law of Motion
“An object at rest tends to stay at rest and an object in
motion tends to stay in motion unless acted upon by
an unbalanced force.”

28. Newton’s First Law of Motion
With no net force acting upon it, an object at rest tends to
stay at rest, an object in motion tends to stay in motion.
Both objects will continue with the same inertia keeping the
same velocity.
• A soccer ball doesn’t just roll
across the field on its own.
• It takes a force (such as a
kick) to move the ball.
• Once the ball moves, it
doesn’t just move forever.
Eventually it will stop.
• Earth’s gravity and friction
stop moving objects.

29. Newton’s Second Law of
Motion
The acceleration of an object depends on the
mass of the object and the size of the force
acting on it.
Acceleration: a measurement of how quickly an
object is changing speed.

30. NEWTON’S SECOND
LAW
The more mass an object has, the
harder it is to accelerate.
The less mass an object has, the
easier it is to accelerate.

31. Newton’s Third Law of Motion
“For every action there is an equal and opposite
reaction.”

32. Forces occur in pairs-
for every action there is an = and
opposite reaction.
As the runner’s foot
pushes on the
starting block
(action force), the
starting block is
exerting a force on
the runner’s foot
(reaction force).

33. Let’s Review
A(n) __________ is a push or a pull.
B) motion
D) velocity
F) Acceleration
D) force

34. Let’s Review
• Which of the following is not an acceleration?
• A) stopping your bike at an intersection
• B) slowing your bike ride so you can make it up a hill
• C) riding your bike faster when you head down a hill
• D) riding your bike straight down the street at a constant
speed

35. Let’s Review
Forces that cancel each other are called __________ forces.
• A) neutral
• B) balanced
• C) inactivated
• D) null

36. Let’s Review
• Whenever one object exerts a force on another
object, the second object ALWAYS exerts an
equal force back on the first object.
• A.) True
• B.) False

37. Let’s Review
• Forces always occur in ______________.
• A.) Triplets
• B.) Pairs
• C.) by themselves
• D.) either singly or in pairs

38. Let’s Review
• Newton's first law of motion states that __________.
• A) an object will remain at rest or keep moving with a
constant velocity unless a force acts on it
• B) acceleration is calculated by dividing the force exerted on
an object by the mass of the object
• C) when a force acts on an object, its acceleration is in the
same direction as the force
• D) when a force is applied on an object, there is an equal
force applied by the object in the opposite direction

39. Let’s Review
__________ is a force that resists motion between two
surfaces.
• A) Resistance
• B) Inertia
• C) Friction
• D) Acceleration

41. Essential Question: Why do we need
simple machines? What are the 6
simple machines?
Work means that we are exerting force and moving something.
The 6 simple machines make our work easier. We won’t have to
use as much force with our simple machines.

42. The Wheel and Axle
• Two or more wheels are
connected by an axle
• The wheel turns with or
around the axle

43. Pulley
• A pulley is a wheel with a rope running over
it. The wheel has a groove, called a sheave,
and it keeps the rope from slipping off the
wheel.
• Remember, since there is a wheel in a
pulley there also has to be an axle!

44. Lever
• There are two parts to a lever:
• The Lever Arm: the arm that moves
• Fulcrum: the support or balance
that does NOT move

45. The Wedge
• A wedge is a special kind of inclined plane made of two
slopes, back to back.
• Wedges can be used to move things apart.
• Wedges can change the direction of the applied force.
• A wedge is used to split, tighten, or secure a hold.
• A wedge is usually a triangle shape with a sharp point.
• If you apply force at one end, the wedge will go
between something, in this case an ax splits a piece of
wood.

46. The Inclined Plane
• The inclined plane is a plane
surface set at an angle, other
than a right angle, against a
horizontal surface. The inclined
plane permits one to overcome a
large resistance by applying a
relatively small force through a
longer distance than the load is
to be raised.
• A screw is a rod with an inclined plane
wrapped around it.
The spiraling inclined plane forms ridges
which are called threads.

47. Let’s Review
Which of the following is NOT a simple
machine?
A.) inclined plane
B.) wedge
C.) elevator
D.) screw

48. Let’s Review
A fork is an example of a:
A.) pulley
B.) wedge
C.) wheel and axle
D.) lever

49. Let’s Review
A saw, a knife, and a doorstop are all
examples of what type of simple
machine?
A.) inclined plane
B.) wedge
C.) pulley
D.) screw

50. Let’s Review
A teeter totter on the playground is
an example of what type of simple
machine?
A.) lever
B.) wedge
C.) pulley
D.) inclined plane

51. Standards Covered
• SC.C.1.2.1- The student understands that the
motion of an object can be described and
measured.
• SC.C.1.2.2- The student knows that waves
travel at different speeds through different
materials.
• SC.C.2.2.1- The student recognizes that forces
of gravity, magnetism, and electricity operate
simple machines.
• SC.C.2.2.4- The student knows that the motion
of an object is determined by the overall effect
of all of the forces acting on the object.