1. OK everyone get ready to learn a new vocabulary term.

2. Force
Today we are going to be defining force.

3. Gravity
We’ll also define gravity,

4. Mass
mass,

5. Weight
and weight.

6. Before we begin defining new terms, let us review some key words we should already know, and make sure you are firm in your understanding.

7. Matter
Matter takes up space and has mass. Matter is a liquid, gas or soap

8. Grams
Grams are used to measure mass.

9. Let’s review.

10. What unit is mass measured in?
grams

11. What are 3 states of matter?
Liquid, Gas, solid

12. Force
Now, let’s define what force means

13. force: a push or pull on an object.
Force is a push or a pull on an object.

14. Force
Contact
Noncontact
There are 2 types of forces that can be applied.

15. Force
Contact
Noncontact
The first is a contact force.

16. contact force: push or pull applied by touch.
A contact force is a push or pull applied by touch. Here the girl is applying a force to the car to push it forward.

17. Earthquakes
When earth’s plates move, the contact force causes earthquakes.

18. Force
Contact
Noncontact
The second is the noncontact force.

19. noncontact force: pushes or pulls without touching it.
A non-contact force is a push or pull on an object without touching it. Gravity is an example of a non-contact force. We will learn more about gravity in this lesson.

20. What are the 2 different types of forces?
Contact and noncontact.

21. If I am opening my fridge, what type of force am I applying?
Contact
Noncontact

22. If I am opening my fridge, what type of force am I applying?
Contact
Noncontact

23. If my pencil falls to the ground, what type of force is being applied?
Contact
Noncontact

24. If my pencil falls to the ground, what type of force is being applied?
Contact
Noncontact

25. Gravity
Now, let’s define what gravity means.

26. gravity: a non-contact force that occurs between all objects that have mass
Gravity is a non-contact force that occurs between all objects that have mass.

27. gravity: a non-contact force that occurs between all objects that have mass
Let’s take a closer look at mass.

28. Mass
Now, let’s define what mass is.

29. mass: amount of matter in an object
Mass is the amount of matter an object has. It is usually measured in kilograms.

30. Here gravity exists between the apple and earth. Both have mass.

31. Weight
Now, let’s define what weight is.

32. weight: is the gravitational force exerted on an object.
Weight is the gravitational force, or amount of gravity, exerted on an object.

33. Scales measure weight.
When you are measuring your weight, you are measuring the force exerted on you by the earth.

34. You weigh 10% less orbiting the earth
You weight 10% orbiting the earth than you do standing on the earth.

35. 100 lbs
90 lbs
If you weighted 100 pounds on earth, you would weight 90 pounds orbiting the earth.

36. Your mass does not change.
Mass is NOT affected by gravity. Your mass does not change where are you are.

37. Weight is relative
Weight is relative to what and where you are measuring.

38. mass ≠ weight
Mass is not the same as weight.

39. Let’s review everything we’ve covered today.

40. Gravity is an attractive force between objects that have ______.
Volume
Mass
Distance

41. Gravity is an attractive force between objects that have ______.
Volume
Mass
Distance

42. Gravity is an example of a ________ force.
Contact
Noncontact

43. Gravity is an example of a ________ force.
Contact
Noncontact

44. True or False: Weight changes based on the gravitational force

45. True

46. Are mass and weight the same thing?
Yes No

47. Are mass and weight the same thing?
Yes No

48. What are the 2 different types of forces?
Contact and noncontact.

49. What is an attractive force between objects that have mass?
Gravity

50. Remember!!!
So remember!
<keep this slide>

51. force: a push or pull on an object.
Force is a push or a pull on an object.

52. gravity: a non-contact force that occurs between all objects that have mass
Gravity is a non-contact force that occurs between all objects that have mass.

53. mass: amount of matter in an object
Mass is the amount of matter an object has. It is usually measured in kilograms.

54. weight: is the gravitational force exerted on an object.
Weight is the gravitational force, or amount of gravity, exerted on an object.

55. Thanks for watching, and please continue watching CAPs available from this website.

56. Questions or Comments to Michael Kennedy, Ph.D.
This Video Created With Resources From:
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Curry School Foundation’s Research and Development Fund
Questions or Comments to Michael Kennedy, Ph.D.