Nature Journaling - Perennials in your Nature Area

 The perennials have the advantage of having all the food they stored last year so they can grow early and very quickly in the spring when they wake up. 

Your job this week is to find two interesting perennials in your natural area and draw what their growth looks like so far this spring.  

One should be Woody Stemmed, and one should be herbaceous stemmed with new growth coming from the ground since only the roots survive the winter. 

Be sure to take note of which plants you draw so you can come back in a month and revisit the same plant to see how it has progressed.  Try to really capture details! Look close! Use words to describe them because they will be changing a LOT in the next few weeks.  

Here are my examples: The first is in progress, showing how you should use a regular pencil to capture the shape and proportion and to label you drawings. 

The second is closer to being finished with some added color and more labels describing what I was seeing. 

Choosing your Natural Area to study

Over the next few weeks we will be studying Ecosystems in class and thinking about how organisms can still be wild and live and grow even in the City of Chicago where humans have changed the environment drastically. 

In order for you to do your own study, your homework this week is to identify an interesting natural area near your house that you can get to without any trouble at all. As you think about what spot to choose, keep these things in mind. 

 - Easy Access  - Be sure that you can get to this location easily and quickly so that you can visit it when your family's schedule and the weather give you a window. Don't choose an area that is going to be a hassle for you or your family. Good options are your yard, your neighborhood park, or areas along your street where animals and plants are growing and living wild. 

 - Make sure you can identify a number of different plant and animal populations that live in your natural area even if it's very small. (We will try to identify the organisms you are observing, but it's ok if you are not sure the actual species names. "Tall grasses, red ants, a rabbit, Pine tree, moss"  - these can be specific enough for this project. 

 - Make sure that your natural area has at least one woody stemmed perennial like a bush or a tree. Something that has bark. 

- Spend some time in a few different areas before choosing so that you know you have found an interesting natural area to spend time observing. 

Once you have chosen your location, complete the description page we set up in our journals. 

If your natural are is very large like a park, be sure to describe what part of it you will be focusing your work in. 

Here is a picture of the blank journal set up if you forgot to take yours home. 

Writing your conclusions from the Turbine Experiment

Data collection is over, we've analyzed the numbers using some math skills and by drawing and interpreting our graphs, so and now you know a few things.  The data is your  Evidence to use to support your conclusions.  Use it!

First - You know which blade design produced the most voltage and at what angle.  You also know if that set ALWAYS produced more voltage or if your data overlaps at the other angles

Second - You know if your blades followed the trend we noticed in the lab.  The most voltage was often produced by blades tilted at a small angle. (For just about every blade design)

As you think about WHY your two sets of blades worked the way they did, keep these things in mind:

Putting the blades at a small angle increases the area that the wind is hitting, increasing the force that is helping to spin the generator.

but.....

When the hub spins, the blades have to work to move sideways through the air because they produce drag (air resistance/friction).

and.....

Blades that are tilted at larger angles have to push through more air so they produce even more drag than small angles.

and.....

Newton's 2nd law says it will take more force to spin larger and more massive blades, but if they get spinning, they will have more MOMENTUM to help fight through the drag of air resistance.

and.....

The tips of longer blades have to travel around a larger circle than the tip of smaller blades. 





Start your draft in class once you are done with your graph. 

Paragraph 1 - Describe the experiment, Summarize the results and explain your thinking about them.

• Describe the variable you and your partner tested and the design of your blades. 
• Restate your hypothesis. 
• Which set of blades was able to produce the most voltage and at what angle?
• Did this set of blades produce more voltage at ALL the angles we tested? If not, which angles did the other set of blades "win"? 
• Was your hypothesis supported?  Did the variable you changed about the blades have the effect you thought it was going to or did the results surprise you?
• Use what you know about Forces, Drag, and Newton's laws of motion to try to explain why one set of blades was able to spin faster and produce more voltage than the other.  

Paragraph 2 -  Data Analysis. Describe patterns in the data and use calculations to compare the data, along with your own observations, to explain how clear and convincing your data is.

• Is there a clear difference between the amount of voltage your two sets of blades were able to produce or did they produce almost the same voltage?
• How big was the difference between the two sets of blades and the MEAN voltage they were able to produce at the angles we tested? (Use Subtraction to compare!)
• Which set of trials had the HIGHEST range and how high was it?  
• Do you think the data is consistent enough for us to trust  or are there patterns that make you skeptical? 
• What were some of the issues with our equipment that you and your partner encountered when running the tests that might make us trust your results a little less? 

Paragraph 3 - What are your thoughts on how we could improve or change this experiment? 

• What variables were the hardest to control when running this experiment?
• Were there problems with your blade construction?
• How could we fix any problems we had with our equipment to make the test more fair?
• What other blade designs would you be interested in testing if we were to start this process over again?  
• What other variables besides the blade design could we test to see how much they affect the voltage a turbine can produce?

Your conclusions tell the story of the experiment and what you were thinking along the way. 

Be sure to use specific language to clearly explain yourself and include the evidence and FACTS that you think are important to support your ideas and opinions. 

Here are some examples of how to write about the results:

"My partner and I decided to test the overall size of the blades in the turbine. We used a thick cardboard and made our blades rectangle shaped. The control blades had an area of 50 square centimeters and the experimental blades were larger with an area of 90 square centimeters. My hypothesis was that the larger blades would spin faster because.....(thinks about Newton's laws and where the air is going)"

"When you look at the results you can see that the larger blades spun faster at 40° and produced 0.025 more volts at that angle. The smaller blades produced more voltage at every other angle. The most voltage the small blades produces was 0.895 volts at 15°which is 0.090 more volts than the large blades were able to produce. This is not a big difference, but I think it is a clear one because all three trials from the small blades were had more volts than any of the trials with the long blades. The large blades best angle was also 15°."

Our data was mostly consistent with small ranges of only a few thousandths of a volt. The largest range in a set of trials was our large blades at 30° with a range of 0.125 volts. If we had more time i would have retested that angle. I think that we might not have used the protractor correctly and one of the blades might have been at a different angle.

We noticed that our generator and tower wobbled whenever we tested our larger blades. This could be because....

One of our smaller blades was damaged during the testing and we had to re-glue the dowel rod two times. This might have changed how much the blade weighs.

If we started over I would like to design blades that have a curved edge. I also noticed that some other blades had shorter dowel rods and I think that might be interesting to test as well.

Graphing your Turbine Data

 In case you forgot your graph at school or didn't have time to get strated, here is how we set up the axes so you can create your graph before your next class.   

Choose how to label the y-axis so that your highest mean voltage will be graphed near the top of the graph paper. (Many students are numbering by .1 volts.) 

You might need to add your extra angle if you tested one. Be sure that it is in the correct location on the x-axis. 

Graph your means for each angle on the graph by placing TWO dots on the line above each angle you tested. Choose two different colors for the dots showing the data from your Control and Experimental Blades and make a key so we know which is which.

You and your partner collected the data so YOU two are the source for the data.   

Remember, we are going to talk about how to connect the dots using a "best fit line" in class so 

DO NOT CONNECT THE DOTS OF YOUR GRAPH!

Turbine Hypothesis - homework.

Now that you and your partner have your question clearly stated and your blades are (mostly) constructed, and we have a good idea of how the trials will be run, you need to formally write your hypothesis.

A hypothesis is both a prediction of the results and your reasoning. Remember, we've learned a little bit about how the blades interact with the air. We need to angle them to get that unbalanced force to get them moving.   The farther you angle them, they will have more drag they will experience as they cut sideways through the air. Larger blades will both catch more air (more force) and have to fight through more air (more drag).

Use the page in your journal that we set up to detail your Hypothesis:

1. Clearly sate your experimental questions:

We designed a set of blades to answer this question:

Does ______________________________  (fill in the blank with your detailed Independent Variable) affect how fast the turbine will spin and the voltage it will create?

2. Draw and label a small diagram of your blades that details Shape, Area, Material and Dowel Rod Placement, 

3. Predict the results of the experiment:

Which group (Control or Experimental) do you think will spin the fastest and WHY you think it will spin faster than the blades in the other group.

BE SURE TO EXPLAIN YOUR SELF FULLY! Use some factual evidence, either from your observations of your blades or from what you know about how turbines work or what you know about Newtons Laws.

We other scientists need to know exactly what you think so we can decide if your ideas are the same as ours or if we want to argue with you.

Bring in your thoughtful hypothesis (in your journal) to your first science class next week when we will begin testing the turbines and measruing how much voltage they create. 

Experimental Design Vocabulary -

Experimental  Design Vocabulary List

Experimental Question – A testable question that asks how a change you make might affect the results or what happens. 

“If we change this.... does it affect that?”

Hypothesis – What you expect to happen to the results based on the change you will make and

other evidence you have gathered.

Variables – Anything that could change during an experiment that might affect the data and results.

Dependent Variable – What scientists measure to see if it has changed during the trials. This becomes your data f

or the experiment. 

Independent Variable – The variable that is being tested. Scientists carefully change it on purpose to see the effect

it will have on the data and results. 

Controlled Variables – All the other variables that are kept the same to be sure that they do not have any effect.

This makes the experiment a fair test. 

Procedure – Step by step directions for how to run a set of trials. Each trial gathers one piece of data

and observations 

Control Group – A set of trials where the Independent Variable is NOT being changed and tested. 

Experimental Group – A set of trials where the Independent Variable IS being tested. The I.V. is changed on purpose

and the results are then compared to the control group.

Data Table – A chart for recording and organizing the data and calculations.

Graph – The data presented in visual form using bars or lines. 

Data Analysis – Objective, mathematical thinking about the data.

Observations – Objective Statements about what scientists noticed during the trials.  Can be used as evidence.

Conclusions – Subjective thinking and analysis of the results. What scientists think about the results of the

experiment. 

Repeatability – The ability for other scientists to follow a procedure and get similar results.