In this project - we're once again focusing on the experimental process and focusing on an experiment on the hypothesis - or how you think the pipe is designed.
What we observed was that when you pulled on the ropes, two things happened.
- The pipe would move in only one direction.
- The rope on one side would pull out twice as long as the other side.
- Why does the string pull the pipe in only one direction?
- Why does the string pull out twice as long on one side more so than it does the other?
(This is where you put in your own idea of how the pipe works on the inside and draw a quick model that best explains the phenomena you witnessed. One such example of a hypothesis is listed below).
- What I think is going on is that there are two ropes - each with a slip knot that is tied to each end inside the pipe. One of the knots is closer to the side of the pipe than the other; which explains why one side comes out longer than the other, and should explain why the pipe moves in only one direction.
- What we're testing for is if... (restate your hypothesis)
- To test this, we're going to:
- List first step of your experiment
- List second step in the experiment
- Keep listing all of the steps of your experiment
- End with what you are either observing for or measuring.
- If our hypothesis is correct, we should expect to see...
- (Either restate the phenomena or other aspect of prediction that makes logical sense.)
Here's an example:
- What we're testing for is if there are two slip knots tied on the inside of the pipe.
- To test this, we're going to:
- Take two pieces of rope and tie a slip knot to the other on both ends.
- Place the section that is tied together and insert it into the pipe.
- Insert the rope through the cap ends and fasten the cap ends to the pipe.
- Pull on the rope and measure how much rope comes out of one side.
- Repeat for the other side by pulling the rope on the other side and measuring how much rope comes out of that side.
Results & Reflection:
In this section, do a free writing activity that reflects on the little discoveries you've made as you've experimented with your pipes design and other people's experiment.
Write about what you've observed and learned about how your design / hypothesis worked through your experiment.
Ask yourself, what worked? What didn't work?
Discuss if your hypothesis needs to be changed - if so - how would you modify it so that it would better explain how the phenomena works?
What further tests would you run that would validate your new ideas?
- "As we were experimenting - what we noticed was..."
- "What we learned was..."
- "What worked was..."
- "What didn't work was..."
- "What this means is..."
- "How I would modify my hypothesis would be..."
- "What we think is going on is..."
- "If I were to run another test, I would..."
While I was running my experiments - what I noticed was that when I tied the two knots together as illustrated, and placed the knots to one side, it worked. I got a short amount of rope on one side, and a longer bit of rope on the other. The problem that I faced later, was that I had to pull my pipe apart to reset the knots - when I didn't have to do that with the one we're trying to duplicate. What this means is that my design is fundamentally flawed. I still think there is a slip knot inside, but I'm not sure how just yet. I did notice a notch later in the pipe. Perhaps if I tried to fasten one end of the rope to that notch somehow, I could get this thing to work. Perhaps, what I could do is have the rope start from the notch and go inward into the pipe, then have it come back outward somehow. If I did this, then I would need another rope attached to it where the rope turns around. Perhaps this is where I need to tie my knot.