DAY 14

WARM-UP

Click the LINK

Match the graphs on your handout to those in the link

CLASSWORK

1. HW Review

    Acceleration?

    #010A: Lab 2 questions and graphs.

    warm-ups

2. #014A: Penny Acceleration Lab

    Hypothesis

    Data Collection

    Results?

3. Kinematics Equations

    How do we find velocity, position, or acceleration using math?

    LINK - go to pg 37 (section 5.3 Acceleration)

    Copy the equations into your notes

4. Practice Kinematics Problems

    Handout Solve 1 & 2

HOMEWORK:

Complete #014B Kinematics Worksheet #1 and

Complete #014C Rearranging the 5 Kinematics Equations

09/15/16

WARM-UP: Constant Velocity

Think about assumptions you made during your constant velocity experiment. 

A. List at least three assumptions 

(example, the battery is not perfectly round)

B. Choose one of your assumptions, explain it in a sentence, and write what affect it might have had on your results.

(example:  The label has an edge that bumps the ground each time the battery rotates. That impact would increase rolling resistance, and slow the battery down slightly)

CLASSWORK:

1. Position v. Time

    HW Review

2. Velocity Inquiry Lab (20min)

TITLE: Constant Velocity

Your team will design an experiment to compare the position of an object moving with constant velocity over a series of time intervals.  Discuss with your group the variables that will need to be measured to prove that an object is moving with constant velocity.  Decide which variable being measured will be dependent and which will be independent.  

Measurement Equipment

You will have access to several pieces of lab equipment.  There are ball bearings, ramps, meter sticks, rulers, etc.  You may use objects from home if you like.  Make a list of all the equipment you expect to use.  You are allowed to make changes during the lab.  

Discuss with your group how you could take the proper measurements to prove that your object is moving with constant velocity.  Put together a list of procedures that you will follow.  Perform at least three trials.  

Graphing

After you take your measurements, construct a graph of your data and draw a best fit line. Use Google Sheets via your school Google account, and share your graph with me  Construct one graph for each set of data that you take.  Calculate the slope of the best fit line.  

Percent Error

When you have calculated the slopes, take an average of the three values measured without the phone.  Also take an average of the three values measured with the cell phone.  Now compare the average value with the value that is farthest from the average.  You can calculate your percent error as follows:

percent error = (average - outlier) x 100

                                average

For all scientific experiments we aim for a % error that is less than 5 and preferable less than 1.  The smaller the better.  How did your team do?  Answer the following questions.  

1. What sources of error did you identify during your experiment?  

2. How many sources of error were sources that your team had control over?

3. For each of the sources of error you identified above, suggest a possible way to change the experiment to minimize that source of error.

Lab Report

http://www.chem.ucla.edu/~gchemlab/labnotebook_web.htm

Choose roles: https://docs.google.com/spreadsheets/d/1dGGqrsv05QiIc_LKSh15f-LkLtV4pKCmXYZIih_i7BE/edit?usp=sharing

Lab Rubric: https://drive.google.com/file/d/0B31ORq_bI3-VejR5a3czT1Azb1U/view?usp=sharing

Introduction

Materials:  List all the materials used in your experiment.  

Procedure:  List all steps that your group followed in this experiment.  Include diagrams of your experimental setup.  Your procedure should be detailed enough that another group could follow your steps and get the same conclusions.

Data:  Data should be listed in data tables.  There should be one data table for each trial.  

Analysis:  Graph your data.  There should be one graph per data table.  Calculate the slope for each graph.  Take a mathematical average for the slopes.  Use the average slope to write an equation that for the line.  Calculate the percent error for your data.  Answer the analysis questions.  

1. What sources of error did you identify during your experiment?  

2. How many sources of error were sources that your team had control over?

3. For each of the sources of error you identified in problem two, suggest a possible way to change the experiment to minimize that source of error. 

Conclusion:  Answer the following conclusion questions.  

1. What is the relationship between x and t for constant v?

2. Were you able to achieve constant velocity? How can you tell?

Watch: https://edpuzzle.com/media/5786c3f41a8ae5c908e383b8

Answer the questions, and solve/copy the problem

Quiz on Velocity Monday. Review sections 2.1, 2.2, and 2.3

3. Constant Acceleration Lab

Our goal now is to determine the relationship between position and time for an object experiencing a constant acceleration.  Our secondary goal is to use a video to analyze the data, so that more precise data points can be taken.  

Constant Acceleration

Your team will design an experiment to measure the relationship between distance and time for an object with a constant acceleration.  Discuss with your team the experimental setup you will use and the assumptions you will need to make.  

Materials

You will have access to the 50 gauge ball bearings again.  You will also have access to the low friction carts and tracks.  Make an equipment list based on your experimental design.  You must also choose which data collection method you wish to use for this lab experiment, eyes or camera.  

Graphing

The graph of this motion will not be linear.  Your group will need to regress the graph to a straight line and then measure the slope.  As before, measure three separate trials of at least 10 data points each.  Then get the average slope and use it to form an equation.  Include a calculation of the percent error in your experiment.  

Lab Report

Procedure:  List all steps that your group followed in this experiment.  Include diagrams of your experimental setup.  Your procedure should be detailed enough that another group could follow your steps and get the same conclusions.

Data:  Data should be listed in data tables.  There should be one data table for each trial.  

Analysis:  Graph your data.  There should be one graph per data table.  Calculate the slope for each graph.  Take a mathematical average for the slopes of the data.  Use the average slope to write an equation that for the line.  Calculate the percent error for your data.  Answer the analysis questions.  

1. What sources of error did you identify during your experiment?  

2. How many sources of error were sources that your team had control over?

3. For each of the sources of error you identified in problem two, suggest a possible way to change the experiment to minimize that source of error. 

Conclusion:  What is the relationship between x and t for constant a?

Warm-Up. (you'll need a textbook for part of this)

1. For each of these graphs, describe the motion of the person depicted:

2. What are the similarities and differences between average acceleration and instantaneous acceleration?

3. Which metric units would we most likely use to measure the speed of a runner in a 100m dash?

4. If we use m/s to represent velocity, which metric units would we use for acceleration?

Example Problem #1

pg 60

- think about how accel from gravity will be different from the runner's acceleration...

Constant Acceleration

Our goal now is to determine the relationship between position and time for an object experiencing a constant acceleration.  Our secondary goal is to use a video to analyze the data, so that more precise data points can be taken.  

Constant Acceleration Lab

Your team will design an experiment to measure the relationship between distance and time for an object with a constant acceleration.  Discuss with your team the experimental setup you will use and the assumptions you will need to make.  

Materials

You will have access to the 50 gauge ball bearings again.  You will also have access to the low friction carts and tracks.  Make an equipment list based on your experimental design.  You must also choose which data collection method you wish to use for this lab experiment, eyes or camera.  

Graphing

The graph of this motion will not be linear. As before, measure three separate trials of at least 10 data points each. 

• Make a position vs. time graph for each trial 

• For your best trial, use your time and distance data to calculate the average velocity through each interval. 

• Make a graph showing the velocity vs. time for your best trial

• Then use the change in velocity from one interval to the next, and the change in time from one interval to the next to solve for the acceleration ( a=Δv/Δt ) between each interval. 

Lab Report

Procedure:  List all steps that your group followed in this experiment.  Include diagrams of your experimental setup.  Your procedure should be detailed enough that another group could follow your steps and get the same conclusions.

Data:  Data should be listed in data tables.  There should be one data table for each trial.  

Analysis:  Graph your data.  There should be one graph per data table.  Calculate the slope for each graph.  Take a mathematical average for the slopes of the data.  Use the average slope to write an equation that for the line.  Calculate the percent error for your data.  Answer the analysis questions.  

1. What sources of error did you identify during your experiment?  

2. How many sources of error were sources that your team had control over?

3. For each of the sources of error you identified in problem two, suggest a possible way to change the experiment to minimize that source of error. 

Conclusion:  1. What is the relationship between x and t for constant a?

                        2. Did you get a constant a?