Download unit: describing motion

8th Grade Science
First Semester Study Guide
Mrs. Keyes
Note to students: Your semester exam will cover everything that we have done so far this year.
While this study guide is designed to help you study, be sure to also look over your content quizzes, unit tests, lab activities,
Gizmos, ISN and textbook. Extra credit will be given for FULL completion of this study guide.
UNIT: SCIENCE BASICS
1. Be able to identify and describe the use of various scientific tools.
2. Given a scenario, be able to identify the safety rules/guidelines which were broken and/or followed.
3. What is the number one safety rule for science students to follow?
4. Review the “What is Science” Vocabulary. (ISN pg.9)
5. Explain the differences between the old scientific method and the new activity model for science. Which is more
realistic in daily science investigations? Why?
6. What is a(n)…Independent Variable? Dependent Variable? Controlled Variable? Control Group?
In a scenario, be able to identify each of these items.
7. Be able to distinguish between inferences and observations.
8. Be able to distinguish between qualitative and quantitative observations.
9. Know how to correctly make a Data Table.
a. Know where to put the independent variable and dependent variable.
b. Know how to properly form a title.
c. Be sure to include appropriate units.
10. Know how to correctly make a Graph.
a. Know where to put the independent variable and dependent variable.
b. Know how to properly form a title.
c. Be sure to include appropriate units and choose appropriate scale for axes.
11. Be able to read BOTH a Table and Graph for important information essential to a Scientific Question.
UNIT: DESCRIBING MOTION
Text: Lesson 1: Motion and Speed
Lesson 2: Acceleration
12. How do you know if something is moving?
13. Be able to describe the motion of an object by the position of the object in relation to a reference point.
14. Define reference point. When is one used?
15. What is speed?
16. What is the equation for average speed? Why would I want to use average instead of instantaneous speed?
Be able to use this formula to solve problems given two of the variables.
17. In a distance-time graph, what does the steepness of the graph (slope) indicate?
18. What is the difference between a scalar quantity and a vector quantity?
19. What is the difference between speed and velocity?
20. What is average velocity? Give an example.
21. What is resultant velocity? Give an example.
22. What are the main differences between a distance-time graph and a velocity-time graph? (Review Gizmo!)
23. Define acceleration. What is the relationship between velocity and acceleration?
24. How do you calculate average acceleration? Be able to use this formula to solve problems given two of the
variables.
25. Define centripetal acceleration.
26. Be able to interpret speed, velocity, distance, and acceleration on a graph.
UNIT: FORCES
Text: Lesson 3: Forces
27. What is a force? How is it measured (what unit)?
28. Explain and give several examples of both Contact and At-A-Distance (non-contact) forces.
29. Explain net force. How do you determine the net force on an object if all the forces act in the same direction? In
different directions?
30. Explain the difference between balanced and unbalanced forces. What do they look like?
31. Be able to create a free-body diagram for a specific scientific scenario.
a. ALWAYS include Gravity
b. What will the FBD look like if moving at a constant velocity?
c. What will the FBD look like if it is accelerating?
32. Be able to describe possible scenarios given a free-body diagram.
33. What is friction? Why does friction occur?
34. In which direction does friction work? Why?
35. How does the roughness or smoothness of a surface effect friction?
36. What is the difference between kinetic and static friction? Give examples of each.
37. What are some ways to reduce friction? Increase friction? Why would you want to change the amount of friction?
Newton’s Laws of Motion: 1st Law
38. State Newton’s First Law of Motion.
39. Provide an example related to the 1st Law of an object at rest.
40. Provide an example related to the 1st Law of an object in motion.
41. What is an unbalanced force?
42. What unbalanced force is commonly used in the 1st Law?
43. What alternative name is often given to Newton’s 1st Law?
44. Define inertia and give an example of how it works.
45. How is mass related to inertia?
a. The larger the mass…

Give an example of this situation.
b. The less mass…

Give an example of this situation.
Newton’s Laws of Motion: 2nd Law
46. State Newton’s 2nd Law of Motion.
47. Identify the equation associated with this law.
c. Be able to use the equation and identify all variables appropriately.
d. Be able to rearrange the equation to solve for the unknown variable.
48. What two variables does acceleration depend upon?
a. Give two examples of how acceleration depends upon MASS.
b. Give two examples of how acceleration depends upon FORCE.
49. How can I increase the acceleration of a grocery cart that is pushed with a set amount of force?
50. What is the acceleration of a 7kg mass if a force of 68.6N is used to move it?
51. What force is necessary to accelerate a 1,250kg car at a rate of 40m/s2?
Newton’s Laws of Motion: 3rd Law
52. State Newton’s 3rd Law of Motion.
53. Describe how a swimmer moves through the water.

If the swimmer is pushing on the water and the water is pushing back on her WITH EQUAL AND
OPPOSITE FORCE (net force = 0N…right???), why does she move forward?
54. Be able to provide several examples of action and reaction force pairs.

How does the reaction force cause the object to move?
Lesson 4: Gravity and Motion
55. Define gravity. How does gravity affect matter?
56. What is the acceleration of an object due to gravity (also called g?) What does this number mean?
57. Because weight is a force due to gravity, we use the Formula: F weight= mass * g (this is identical to 2nd law: f=ma)
a. Be able to use the equation and identify all variables appropriately.
b. Be able to rearrange the equation to solve for the unknown variable.
58. Why are some astronomical bodies round, while others are lumpy?
59. Who is the primary scientist that we attribute gravitational research to?
60. What are the two parts of the Law of Universal Gravitation?
61. Explain the difference between weight and mass. How is each measured (units)? How does each change when in
space?
62. What is free fall? Where does free fall occur?
63. Explain the process of orbiting.
64. Define air resistance. How does it affect different sized/shaped objects?
65. What is terminal velocity?
STUDY HARD! STUDY HARD! STUDY HARD! STUDY HARD! STUDY HARD! STUDY!
Good Luck! Good Luck! Good Luck! Good Luck! Good Luck! Good Luck! Good Luck! Good Luck!
“I Can” Statements from Semester One Science…
Science Basics (including safety):
I can...
1) identify necessary safety precautions within a given scientific investigation.
2) identify and describe the use of common scientific tools and safety equipment.
3) recall the meaning of scientific vocabulary and use it appropriately in scientific settings.
4) describe different features and challenges in doing scientific investigations.
5) identify examples where science is not a linear process.
6) determine the variables within a scientific investigation and compare/contrast their
roles.
7) read, interpret, construct, , and analyze data tables, graphs, charts, and other visuals related
to a scientific investigation
Describing Motion
I can...
1) describe the motion of an object relative to a reference point.
2) describe and demonstrate how distance, time, and speed are related.
3) explain the similarities and differences between speed and velocity.
4) define, identify, and calculate varying forms of acceleration (positive, negative, centripetal).
5) analyze and differentiate between speed and velocity in graphs.
Forces
I can...
1) identify and describe different types of forces and explain their effects on motion.
2) describe an object’s motion using Free-Body Diagrams.
3) describe the effect that gravity has on matter.
4) demonstrate my knowledge of forces by designing and constructing a
parachute and carrying device.
5) differentiate between mass and weight.
6) define and explain how inertia effects an object’s motion.
7) explain the relationship between force, mass, and acceleration, according to Newton’s
2nd Law of Motion.
8) identify the action/reaction forces in a given scenario and explain how they affect motion.
9) demonstrate my knowledge of Newton’s Laws of Motion by designing/building a vehicle that
exhibits all 3 laws.