1. Chapter 11

2. Units
Measuring motion
Acceleration
Motion and force

3. Measuring Motion Everything is in motion But how do we observe it?
Need a Frame of Reference
Movement relative to certain points
How do we know that the Earth is moving?
Stars change around us
Displacement
How far an object moves
Must indicate direction

4. Measuring in Motion Speed and Velocity
What is speed?
How does speed relate to velocity?
Speed is how fast, but velocity is speed + direction
Velocity can be described in many ways
How to calculate speed
Do velocity worksheet
Can be combined with different forces

5. Measuring Motion Average speed Instantaneous speed
Do we constantly move at the same speed?
No, we find the average speed over a certain amount of time
Instantaneous speed
Can be measured at any time
Eg speedometer

6. Measuring Motion Average speed Instantaneous speed Over time
An average
Speed=distance/time
Less accurate
speed at a snapshot
At any given time
Very accurate

7. Measuring Motion Motion can be graphed Distance-vertical axis
Time-horizontal axis
Slope equals speed
Slope of line worksheet

8. Measuring Motion Section 1 review Define key terms
Summarize each paragraph
Concept review ws
Quiz next class

9. Acceleration What changes when an object accelerates?
How do you calculate acceleration?
How can you use a graph to find acceleration?

10. Acceleration Velocity has speed + direction
Acceleration is a change in velocity
Change in speed
Change in direction
Circular motion has centripetal force
Eg standing on earths surface
Spinning a coin
Velocity is always changing, even though the speed stays the same
Velocity practice

11. Calculating Acceleration
Calculating acceleration is very similar to calculating speed
Acceleration=change in velocity/time
(final velocity-initial velocity)/time
If you are driving on a road going 60 mph and you have to slow down to 25 mph in 4 seconds because of traffic, then what is your acceleration?
Go over on board
Can apply to any change, wither slowing down or speeding up
Slowing down-negative
Speeding up-positive
Practice problems pg 375
Acceleration packet

12. Acceleration Can be graphed very similar to speed
Speed graph
distance vs. time
Acceleration graph
Speed vs. time
Just like on a speed chart, the acceleration is the slope of the graph between the points you are looking at
Practice problems pg 376

13. Acceleration Answer review questions on pg 377 Concept review ws
Summarize each concept and key terms in your journal
Quiz next period

14. Motion and Forces Fundamental forces? Net force?
What force opposes motion?
Why is friction necessary?

15. Force
What is a force?
Any action that can change the state of motion of an object
Eg kicking a ball or lifting weights

16. Fundamental forces 4 fundamental forces in nature
Gravity
Electromagnetic force
Strong nuclear force
Weak nuclear force
Nuclear forces are what binds atoms together and allow cohesion of molecules
Not noticed in every day
Only over very short distances

17. Fundamental forces Can vary widely in strength
Eg strong nuclear force keeps atoms together, but outside the radius it is negligible
EM force is strongest aside form the strong nuclear force, and can act over great distances
Gravity is less weak than EM

18. force Can act in several ways Contact Field Push and pull
Attraction of gravity or repelling poles of a magnet

19. Balancing forces Forces can cancel out
Net Force is the combination of all the forces acting on an object
object moves in the direction of the net force
If net force is 0 the object doesn't move

20. Balanced forces If the forces are balanced the motion is not changed
Eg the book on your table
Unbalanced forces do not completely cancel, and there can be some movement
Can combine into different directions
Eg north + east = northeast direction
1534/BillNyeMotionWorksheet.pdf

21. Friction Friction Eg car slowing down when you let off the gas
Opposition to motion
Eg car slowing down when you let off the gas
Surfaces are rough
Create heat
Some are less rough than others

22. Types of friction Static friction Kinetic friction
Friction between objects that are stationary
Kinetic friction
Friction between moving surfaces
Force required to make objects moving is greater than an object that’s already moving

23. Types of kinetic friction
Different kinds of kinetic friction
Sliding
Objects moving past one another
Rolling friction
Ball rolling along ground
rolling friction less than sliding
Hence why we use balls

24. Friction and motion Friction is important Allows car to move
Allows brakes to stop a car
Allows you to write with your pencil
To take notes!!
Needed in everyday life

25. Unwanted friction
That dosent mean that all friction is wanted friction
In some ways, it is possible to reduce the unwanted friction
Eg nonstick pan
Lubricants such as grease and motor oil
Even air can act as a lubricant
Air hockey tables

26. Increasing helpful friction
We can increase friction by making surfaces rougher
Eg sand on icy roads
Road salt in case of snow or ice
Wearing gloves to work out or play sports with
Eg batters gloves, receivers gloves
friction increases as the force that pushes the surfaces together is increased
Eg putting a paperweight on something

27. Cars You need friction in order to use cars
Tires push against road, pushing the car forward
With no friction, what happens?
Start sliding
Hydroplaning
Brakes also affect moving objects
Friction of the brakes opposes the force of gravity trying to get the car to move forward

28. What do you need in order to find velocity?
Bellringer
What do you need in order to find velocity?

29. What did you learn from the domino lab?
Bellringer
What did you learn from the domino lab?

30. How do you find the slope between 2 points?
Bellringer
How do you find the slope between 2 points?

31. What is an example of acceleration?
Bellringer
What is an example of acceleration?

32. What goes on the y-axis on an acceleration graph?
Bellringer
What goes on the y-axis on an acceleration graph?

33. What questions do you still have about acceleration?
Bellringer
What questions do you still have about acceleration?

34. What 3 parts make up an atom?
Bellringer
What 3 parts make up an atom?

35. What are the charges on each part of an atom?
Bellringer
What are the charges on each part of an atom?

36. file:///H:/section01/teaching_master1.pdf