HP Cycle 1

🟢 8: T 9/8 - x vs. t and v vs. t graphs

Today, we'll finish checking our understanding of how to read position vs. time (Ostrich) and velocity vs. time graphs (Cheetah) by completing the Ostrich & Cheetah WS.  With any time remaining, you'll work collaboratively on ➕Positive Physics homework (see below).  

Presentation:  Ostrich & Cheetah Presentation

Handouts:  Ostrich & Cheetah WS, Graphic Analysis of Motion WS 

Homework:  Log on to ➕Positive Physics using your school Google account.  In Unit 1: Velocity, do the following "work" sections:

• 1.11 - Graph Concepts

• 1.12 - Graph Problems

• 1.14 - Advanced

These problems will be graded for completing correctly, so only the completion score counts.  You need to get the problems correct in order to get credit, but try the problems till you get them right. This homework is due at 10pm tonight (Tuesday, September 8th).   NO LATE WORK ACCEPTED IN POSITIVE PHYSICS!  ❗ Assessment on all of graphical analysis of motion on Tuesday, September 15th. 

Recommended Additional Practice Problems:  Complete Graphic Analysis of Motion WS (velocity vs. time) by next class.  Make sure to complete the graphs at the bottom of both back and front.  ANSWER KEY.   Also from the textbook: Ch 2 #3, 4, 8, 18, 24, 19, 25, 20, 22, 36 (answer in Mastering Physics so you can see if you're right)

🟩❗8: W 9/9 - velocity vs. time graphs

Today, we'll finish and recap velocity vs. time graphs (Cheetah) by highlighting the fundamental understandings from the Ostrich & Cheetah WS.  We'll find a pattern for the relationship between the velocity vector, acceleration vector, and speeding up or slowing down.  We'll review some vocabulary for describing motion with this presentation - Describing Motion - Kinematics Vocabulary.

Then, we'll take a pre-assessment for the dynamics unit.

Finally, if you have time afterwards, you can start doing your homework below.

Presentation:  Describing Motion - Kinematics Vocabulary

Handout:  Motion Graphs & Linearization

Homework:  First, please read slide 3 of Describing Motion - Kinematics Vocabulary - a summary of the proper physics vocabulary to use on your assessment.  Next, we'll be practicing our graphing skills with the following activity - Motion Graphs & Linearization.  For homework, fill out the position data in the data table using the correct number of sig figs for BOTH motions (front and back).  Think about what measurement needs to be taken:  AB, BC, CD, ... or AB, AC, AD, ...  Then, plot the points in BOTH position vs. time graphs (front and back).  Completed data table and x vs t graphs are due at the start of next class.  No late work will be accepted.  ❗ Assessment on all of graphical analysis of motion on Tuesday, September 15th.  

💚 8: Th 9/10 - motion graphs & linearization

Today, we'll continue the activity where we'll practice our graphing skills - Motion Graphs & Linearization.  In this activity, you will look at the motion of two different objects.  Then analyze the motion by doing the following:

1. Describe the motion in words.  Discuss in your lab group.

2. Predict the x vs. t and v vs. t for trial 1 and sketch it on the whiteboard (no numbers required).  Discuss in your lab group.  

3. Take data and plot position vs. time  for each trial.  Think about what measurement needs to be taken:  AB, BC, CD, ... or AB, AC, AD, ...

4. Take data and plot velocity vs. time  for each trial.  Think about what measurement needs to be taken:  AB, BC, CD, ... or AB, AC, AD, ...  You may use the additional columns to make calculations if you need to.

5. Draw a best fit curve on each of your graphs.  Remember to NOT connect the data points; each data point has a margin of error.  To draw the best fit curve, draw a smooth line or curve that best represents the trend in your data.  If you think the graph is linear, use a ruler to make a perfectly straight best fit curve.

6. If any of your graphs are linear, find the equation of the line.  Find two points for the slope calculation that are far away from each other and circle them.  Then show your calculations to get the slope and find the intercept.  Using the slope-intercept form, write your equation on the same page as your graph.  Remember not to use x and y as the variables in your equation; use the variables on the axes of your graph (e.g. x, v, t ).  All numbers (slope and intercept) should be in decimals with the correct number of sig figs and also have appropriate units.

The final step in our activity may be something new to you - linearization.  In order to find a mathematical relationship between two variables, it is common to graph the data.  If the relationship between the two variables is linear, you can write a mathematical relationship by finding the slope and writing a slope-intercept equation.  However, if the relationship is not linear, finding an equation that relates the two equations is a little more difficult.  While one way to get an equation is with a computerized curve fit, today we will learn how to do it by hand with "linearization."  We'll first read through determining relationships from graphs to review what different curves look like and then figure out how to linearize the graph.

Then, we'll continuing to work with Motion Graphs & Linearization and try to get a linearized the position vs. time graph for trial 2.  What do you think the slope of the linearized graph represents?

Presentation:  Presentations:  What is motion? (slides 6-8, 15-17), Motion Graphs & Linearization Presentation

Handout:  Motion Graphs & Linearization (from last time), determining relationships from graphs

Homework:  Finish Motion Graphs & Linearization. ❗ Assessment on all of graphical analysis of motion on Tuesday, September 15th.  This assessment will only include graphical analysis of motion (big graph homework).  It will not include linearization (activity from today).