# 7 September Science 7 Recap on motion so far; introduction of summative project #1

1. Mindful moment. Think of the motion everywhere and in everything from atoms to galaxies. Another quote from Thich Nhat Hanh: “The miracle is walking on the earth, not walking on water or fire. The real miracle is walking on this earth.”
2. Review previous entry from DSN. Add details or items that you missed.
3. Browse today’s blogpost.
4. Open new document in your DSN for today’s entry. Include the link to today’s blogpost.
5. Questions. Each student should pose a question or questions about what we have learned and introduced about motion so far this year.
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Graphing?

Figuring out the value of average speed for a motion event.

Understanding that average speed is what speed the observed mover would have had if the mover had moved at a constant speed. In the tortoise and hare race, both movers had the same constant speed over the 25 meters. How do we know? They tied!!! The tortoise moved (mostly) with constant speed. The hare’s speed changed much during the race. The tortoise’s graph is going to be very close to the average speed graph. So average speed may not be exactly what really happened, but it is a very useful measure that is fairly easy to calculate and to show on a graph.

Understanding the idea of frame of reference.

Understanding how to describe position.

How to carry out “fair” measurements.

Understanding how time is measured. Thinking about how time relates to motion.

Knowing what errors students sometimes make and making sure to avoid such errors. (Confusing time with speed. Calculating Time/Distance instead of Distance/Time for speed. Scaling errors on graphs. Not using fair timing procedures. Not measuring distance correctly. Others?)

The Tumble Buggy 2018

Summative Assessment Science 7 Motion

Mr. Margenau & Dr. Frazier

3 class meetings for gathering and analyzing data

Final written report due at the before the end of the 4th class (print paper copy and digital copy in G-classroom)

Basic Problem: Determining the velocity (both the speed and the direction) of the “Tumble Buggy” and the extent to which the speed is constant and the direction is straight?

Groups of 3 work together to write procedures and obtain data.

Individuals perform calculations, analyze the results and write individual reports.

You will need to:

Develop methods for determining the speed of the tumble buggy and its direction of travel.

Some things to keep in mind:

• Speed and time are related but they are not the same thing.
• You will need to develop a repeatable and reliable way to start the car and to time its motion. This means that your procedures for gathering data are FAIR.
• You will need to run trials in different directions to find out the extent to which the floor affects the results (floor may not be perfectly level).
• You will need to conduct a sufficient number of trials to establish how reliable and consistent the data are.
• You will need to try various distances to establish whether the speed is constant.
• You will need to measure distance and time carefully, accurately, consistently.
• What will you do if the buggy does not run perfectly straight? Why?
• You will need to generate motion graphs of the results. One type of graph is distance vs. time for speed. Another type of graph could be distance vs. distance to examine how straight the tumble buggy travels.
• You will need to calculate average speeds (distance traveled / time elapsed). Which average speed will you report if the average speed of each trial varies? Median works if you have fewer than 10 trials. Mean can be used when the number of trials are sufficient >10.
• To what extent is the speed constant? If it is not constant, how much does it vary?
• To what extent is the direction straight. If it is not straight, how much does it vary?
• What variables affect the results? What variables do you control?

Communicate findings in a written form (using the following headings)

• Title – Clearly stating what the experiment is about
• Background – What have you learned about motion before this assessment project? Describe experiences and new knowledge. Mention learning about how to measure motion, how to analyze data
• Question (expressed in a clear form)
• Expected answer – (before doing the experiment) and why you expected that answer to the question?
• Methods or Procedures (written in 1st/3rd person and past tense; not written as commands)
1. How was data acquired
2. How was data analyzed (graphs and calculations)
• Results
1. Table of results (organized and labeled)
2. Calculations with correct units.
3. Appropriate, well-made graphs
4. Photos
5. Anecdotal observations.
• Analysis or Interpretation

Relate results to question. How do your results relate to what you expected? Use evidence from your data to support claim of what the speed of the Tumble Buggy is and whether it is constant. Use evidence to support claim about how straight the direction of travel is. Refer to scientific concepts relevant to the problems that we have discussed in class. Discuss the size of any variation in results and factors contributing to it.

• Conclusion Summary and New Questions

Summarize results, suggest new questions and propose new experiments to investigate the tumble buggy and its velocity (speed and direction), motion, and performance.

Meeting—Includes details of practice and reasoning. Makes accurate measurements. Constructs correct graphs and makes correct calculations (including units). Demonstrates understanding of techniques for acquiring and analyzing data relevant to motion. Demonstrates understanding of the concept of average speed.

Standards

Disciplinary Core Ideas

Forces and motion

Cross-Cutting Concepts

Scale, Proportion, and Quantity

Science and Engineering Practices

Planning and Carrying out Investigations

Analyzing and Interpreting Data

Constructing explanations and designing solutions

Obtaining, evaluating, and communicating information.