HP Cycle 3

🟢❗ 5: T 9/19 - graphical analysis of motion review

❗ Mini-Assessment on Position vs. Time graphs TODAY!!!  

After the assessment, we'll finish whatever we have not yet done with the Cheetah.  

Then, in our lab groups, we'll continue the Graphic Analysis of Motion WS (velocity vs. time on page 2).  ANSWER KEY.  We'll review features of position vs. time graphs and velocity vs. time graphs, and you may ask questions if you don't understand.  I will go over special aspects, especially about J-K-L and also H-I-J.  We'll talk about some advanced concepts like how to find instantaneous velocity and acceleration when the graph is curved.  We'll generate a list of phrases we can use to describe the motion given a graph.  

Presentation:  Ostrich & Cheetah Presentation

Handout:  Ostrich & Cheetah WS

Homework:  Make a chart for yourself about the difference between analyzing displacement vs. time graphs and velocity vs. time graphs.  In this chart, you should include answers to questions like: What does a 0 slope mean?  What does it mean to cross the time axis?  What does it mean if you have a positive slope?  This will serve as a study guide for you for the upcoming assessment.  Upload a picture of your chart to ✏️Google Classroom.  ❗ Assessment on all of graphical analysis of motion Friday, September 22nd.

Recommended Additional Practice Problems:  Ch 2 #3, 4, 8, 18, 24, 19, 25, 20, 22, 36 

🟩 5: W 9/20 - creating motion graphs

Today, we'll first review the use of significant figures for lab.  

Today, we'll first watch a demonstration of the creation of a motion diagram.  Then, discover three different methods for getting an instantaneous velocity vs. time graph from your position vs. time data/graphs.  We'll be working with your homework Practice - Getting graphs from TTT data to "transform" your graphs.  

Presentation:  Sig Figs in Lab 

Handout:  Sig Figs in Measurement (3 pages), Practice - Getting graphs from TTT data 

Homework:  For the two different trials on Practice - Getting graphs from TTT data:

1. Describe the motion in words.

2. Predict the x vs. t and v vs. t for trial 1 and sketch it (no numbers required).  Use a separate page for each graph.

3. Draw position vs. time  for Trial 2 only on the 3rd piece of graph paper.  Actually make measurements with a ruler and use the data table for this graph.  Measure for EVERY data point; 

4. Draw velocity vs. time  for Trial 2 only.  You may add a calculation column or two in your data table and show all points.

5. Draw a best fit curve on each of your Trial 2 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 either of your Trial 2 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 an intercept, 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.  All numbers (slope and intercept) should be in decimals with the correct number of sig figs and also have appropriate units.

Questions to think about:

• What will you measure for your data?  AB, BC, CD, ... or AB, AC, AD, ...

• From where to where on each dot will you measure?

• Why will you make separate measurements for each data point?

❗ Assessment on all of graphical analysis of motion Friday, September 22nd.

💚❗ 5: F 9/22 - linearization

❗ Assessment on all of graphical analysis of motion TODAY!

Today, we'll work on our graphing lab skills.  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 Practice - Getting graphs from TTT data and try to get a linearized the position vs. time graph.  What do you think the slope of the linearized graph represents?

Homework:  Make sure you've finished linearizing the position vs. time graph of trial 2 from Practice - Getting graphs from TTT data.  Find an equation of the best fit line for every straight line in your packet (to be collected in class at the beginning of Tuesday's class).  Remember not to use x and y as the variables in your equation; use the variables on the axes of your graph.  All numbers (slope and intercept) should be in decimals with the correct number of sig figs and also have appropriate units.