2. Hey pal it looks like you could use some help.

3. Um Yeah

4. What you need is some force.

5. Oh Yeah!!

7. Thanks!!!

8. A force is a push, pull or twist
Examples of contact forces
A force is a push or pull upon an object resulting from the object's interaction with another object. Whenever two objects are interacting, then some force is acting upon each of the objects. When the interaction stops, the two objects no longer experience any force between them. Forces only exist as a result of interactions.
These 3 images all depict contact forces.
Image sources:
A man playing field hockey: 2005 Michelangelo-36, Wikimedia Commons
A girl kicking a soccer ball: Microsoft clipart
A body tugging a rope: Microsoft clipart
Applying a force can change an object’s velocity.
Applying a force can cause an object to _________.
accelerate

9. Types of Forces
Contact forces: interactions between objects that touch
Non-contact forces: attract or repel, even from a distance
magnetic force
applied force
spring force
electric force
drag force
Introduce students to the different types of forces through simple demonstrations.
Distinguish between contact and non-contact forces.
Show that different types of forces exist in each category.
Give brief definitions of each type of force (direct students to write these definitions in their notebooks) and perform a simple demonstration of each one.
Image sources:
A man hitting a baseball: Microsoft clipart
A metal spring: 2004, Jean-Jacques MILAN, Wikimedia Commons
A cartoon parachute an man; Microsoft clipart
A cartoon girl slipping on ice: Microsoft clipart
A “U” magnet: Microsoft clipart
A cartoon atom: Microsoft clipart
An apple falling from an apple tree onto a man in a suit: Microsoft clipart
gravitational force
frictional force

10. Forces around us
What happens when forces are in equilibrium?

11. Common Forces Force Symbol Function Fg FN FT Ff FK FS Fair Fapp
Gravity Fg
Force of attraction between all objects
Normal FN
Force perpendicular to the surfaces of objects in contact
Tension FT
Force exerted by materials, such as ropes, fibres, springs, and cables, that can be stretched
Friction Ff
Force that resists motion or attempted motion between objects in contact
Kinetic Friction FK
Force that acts against an object’s motion
Static Friction FS
Force that tends to prevent a stationary object from starting to move
Air Resistance
Fair
Frictional force that opposes an object’s motion through air
Applied Force
Fapp
Any contact force not previous included

12. Next we need the units for force

13. UNITS OF FORCE
POUNDS
&
NEWTONS

14. =
(Metric Unit) =

15. A spring scale measures force.

16. A person weighing 100 pounds would weigh 448 newtons
POUNDS vs. NEWTONS
A person weighing 100 pounds would weigh 448 newtons

17. Mass
The amount of “stuff” (matter) in an object.

18. Weight
Gravitational force exerted on an object

19. Mass—A Measure of Inertia
2.2 pounds near Earth’s surface.

20. Mass Weight Measured in kilograms
Does not change from planet to planet
Measured in Newtons
Affected by a planets gravity

21. Concept Review
1. A _____ is a push, pull or twist. 2. Kicking a ball is an example of a __________ force. 3. Newton’s first law of motion: Objects in motion will stay in motion and objects at rest will stay at rest, unless acted on by __________________.
force
contact
an unbalanced force
Review slide for Day 1 material (lesson 1).
Next, administer the exit ticket and homework assignment that correspond to this material.
Day 2 begins with slides reviewing the material from Day 1. The new Day 2 material begins with the slide on Newton’s second law.

23. Deciphering Newton’s First Law
“Every body persists in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by force impressed.”
—Sir Isaac Newton
Principia Mathematica (1687)
Write: In your own words, what does this mean?
Make sure students do not confuse “every body” with “everybody.” Clarify that Newton wrote “every body,” meaning “every object.”
This slide brings in the Common Core.
Image sources:
The cover page of Newton’s book, Naturalis Principia Mathematica: 1687 Wikimedia Commons
A portrait of Isaac Newton: 1689 Sir Godfrey Kneller, Wikimedia Commons
Unless an unbalanced force acts on an object,
An object at rest stays at rest
An object in motion stays in motion
Isaac Newton,

24. Inertia
An object’s resistance to any change in motion

25. Inertia
Big Mass = Big Inertia
Small mass = Small inertia

27. A B

28. ???
What part of a bicycle or car is designed to overcome the law of inertia?

29. Homework # 10
Read pages 44 – 48
Page 63/ Concept Review 1-4

30. Projectile Motion

31. Projectile Motion
The curved path an object follows when thrown near the surface of the Earth

32. Projectile Motion Two parts: horizontal & vertical
Gravity only affects the vertical motion

33. Gravity
A force of attraction between objects that is due to their masses

34. Law of Universal Gravitation
All objects attract each other through gravitational force
Big mass = Big force

35. Here is my second law. I called it NEWTON’S SECOND LAW

36. Newton’s Second Law

37. Newton’s Second Law The acceleration of an object depends
Mass of the object
Force exerted on the object

38. Newton’s Second Law

39. Here is my third law. I called it NEWTON’S THIRD LAW

40. Newton’s Third Law
For every action force, there is a reaction force equal in strength and opposite in direction.