1. Forces and Motion
By: Mr. Hunter

2. Motion
What do you think it means to be in motion? How can we tell if something is in motion?

3. Motion
Motion: a change in position, measured by distance and time. 

4. Motion
Frame of reference: the point from which movement is determined.
To measure movement, some point must be considered as _____ .
_____ is the most common frame of reference

5. Speed only gives distance and time!
Speed: the distance traveled by a moving object per unit of time
To calculate speed, use the equation
Speed = distance / time
Speed only gives distance and time!

6. Average Speed Average speed = total distance / total time
Average speed: the speed of moving objects is not always constant
Average speed = total distance / total time

7. Average Speed
1. What is your average speed if you take 0.5h to jog 4,000 m?
2. If the average speed of a car is 110 km/hr, how long will it take the car to travel 715 km?

8. Graphing Average Speed

9. Velocity Velocity is speed in a given direction.
Velocity gives distance, time, and the direction of travel.
Velocity changes by changing direction or changing speed!

10. Velocity = distance/time (direction is stated in the answer)

11. Speed/Velocity Problems
1. What is the speed of a rocket that travels 9000 meters in seconds?
2. What is the speed of a jet plane that travels 528 meters in 4 seconds?
3. A child is riding on a wagon. The wagon goes out of control at 2 m/s! The child panics and scoots backwards at 0.2 m/s! What is the velocity of the wagon? What is the velocity of the child?

12. Speed/Velocity Problems
4. The space shuttle Endeavor is launched to altitude of 500 km above the surface of the earth. The shuttle travels at an average rate of 700 m/s. How long will it take for Endeavor to reach its orbit?
5. How long will your trip take (in hours) if you travel 350 km at an average speed of 80 km/hr?
7. What is the speed of a walking person in m/s if the person travels 1000 m in 20 minutes? If the person walks south on a northbound train traveling 20 m/s, then what is the person’s velocity?

13. Acceleration = (final velocity – initial velocity) / time
A measure of the change in velocity/ rate of change in velocity
Acceleration = (final velocity – initial velocity) / time

14. 1. Tyler K. and TJ will start out at one side of the room and run to the other. We will measure their distance and time (in seconds).
2. Calculate their speed and velocity.
3. Calculate their accelerations. Which had a greater acceleration.

15. True or false? If you slow down on your bicycle, you accelerate.
If you ride your bicycle at a constant speed, you cannot accelerate.
Changing the speed and changing the direction of your bicycle are both examples of acceleration.

16. Acceleration
1. A meteoroid changed velocity from 1.0 km/s to 1.8 km/s in 0.03 seconds. What is the acceleration of the meteoroid?
2. The space shuttle releases a space telescope into orbit around the earth. The telescope goes from being stationary to traveling at a speed of 1700 m/s in 25 seconds. What is the acceleration of the satellite?

17. Acceleration
3. A dragster in a race accelerated from stop to 60 m/s by the time it reached the finish line. The  dragster moved in a straight line and traveled from the starting line to the finish line in 8.0 sec. What was the acceleration of the dragster?

18. 1. List all of the natural and social constraints you can think of for the design of your balloon car.
2. Brainstorm ideas for structures that you can make with the materials available to you.
3. Draw a picture of your prototype. Explain, in a paragraph, why you think your design will allow your car to be the best!

19. Forces give _____ to objects.
Force: any push or pull.
Forces give _____ to objects.
Forces cause a _____ in motion.

20. Forces are measured in _____ .
A _____ is the combination of all of the forces acting on an object.

21. Forces

22. Balanced vs. Unbalanced Forces
_____ will not cause a change in the motion of an object; they have a net force of ____ N.
Examples of balanced forces are: 1. ______, 2. _____, 3. _____ .

23. Balanced vs. Unbalanced forces
Unbalanced forces could be best described as __________________________ .
Examples of unbalanced forces are ___________________________ .

24. Force Drawing
Create a drawing that shows an example of balanced forces. The drawing should show the forces acting on the object and what happens to the object if the forces become unbalanced.

25. Forces

26. Forces
You and a younger brother or sister are at a neighborhood pool. Your brother or sister asks why there are signs that say “NO RUNNING!” What would be your answer?

27. A _____ is a substance that lessens friction.
Force
_____ is a force that opposes motion between two surfaces that are in contact.
A _____ is a substance that lessens friction.

28. Forces _____ , ______ , and ______ are examples of common lubricants.
Therefore, it is easier to slip when there is water on the floor because the water acts as a ______ that lessens the friction between the bottom of your shoe and the floor.

29. Friction
Two types of friction are _____ and ______ .

30. Friction Pros
Walking
Writing
Driving a car

31. Friction Cons
Makes movement difficult
Wastes energy
Wears things out

33. Friction
Write a story that describes what a day in your life would be like if there was no friction.

34. Gravity

36. Example: You and your books, pencils, paper, etc.
Gravity
Isaac Newton discovered the ______ ______ of Gravitation.
Gravity acts on any objects with mass.
Example: You and your books, pencils, paper, etc.

38. Universal Gravitation Constant
G = 6.67 x N m2/kg2

39. This is the scientific notation for the standard number, 567 000.
5.67 x 105   

40. Scientific Notation Example: 6.03 x 107 = 60 300 000
Write 6.03 X 10 -7

41. Multiplying with Scientific Notation
Ex 1.  Multiply  (3.45 x 107) x (6.25 x 105)
First, rewrite the problem as:   
(3.45 x 6.25) x (107 x 105).
Then multiply the coefficients and add the exponents:    x 1012

42. Multiply
3.04 X 10^ and X 10^8
2.02 X 10 ^ and X 10^56

43. Dividing with Scientific Notation
Rule for Division - When dividing with scientific notation, divide the coefficients and subtract the exponents.  The base will remain 10.
Ex. 1 Divide 3.5 x 108 by 6.6 x 104
rewrite the problem as:                 3.5 x 108                                                                                                            6.6 x 104        
Divide the coefficients and subtract the exponents to get:      x 104

44. Dividing
4.10 X 10^ by X 10^7
56 X 10^5 by X 10^ 5

45. What is the force exerted by Big Ben on the Empire State building
What is the force exerted by Big Ben on the Empire State building? Assume that Big Ben has a mass of 108 kilograms and the Empire State building 109 kilograms. The distance between them is about 5000 kilometers and Big Ben is due east of the Empire State building.

46. The Solution
2.67×10-7N

47. What is the gravitational force that the sun exerts on the earth
What is the gravitational force that the sun exerts on the earth? The earth on the sun? In what direction do these act? (Me = 5.98×1024 and Ms = 1.99×1030 and the earth-sun distance is 150×109 meters).

48. The Solution
3.53×1022

49. Universal Law of Gravitation
Mass and gravity have a directly proportional relationship.
The distance between the centers of masses of the two objects and gravity have an inversely proportional relationship.

50. Fill-In-The Blank
Two bodies of equal mass are separated by a distance R. If you double the distance between them the new gravitational force will be _______________________ .

51. Differentiate between Mass and Weight.
Weight is dependent upon the acceleration due to gravity on a particular planet.
For instance: g on earth is 9.8 m/s²
The larger the planet, the _____ the gravitational force.

52. Determine your weight/ how far you could jump on other planets.

53. Moon 0.17 Mercury 0.38 Venus 0.86 Earth 1.0 Mars Jupiter 2.87 Saturn
1.32
Uranus
0.93
Neptune
1.23