Waves Lab

Waves Lab Maria Turner 7B December 15, 2010

I. GUIDING QUESTION/S (State the guiding question/s): Does the flexibility of the medium affect the amplitude?

II.HYPOTHESIS: We think that it will, because for example if you have a slinky, it is a lot more flexible than a piece of string. The metal tends to go farther than the plastic or string, which is what I’m guessing.

III. Exploration (PLAN & DO A TEST):

Manipulated variable: medium (solids).
Responding variable: wave - flexibility

Materials(in order of most flexible to least flexible):
long slinky
big slinky

big rope

yellow plastic pipe

PROCEDURE:

1. Order all of the mediums in order of flexibility.

2. Take the first medium. Have two people create waves using the medium within a measured distance. You, or the third person, should measure the wavelength of each wave and also figure out what the frequency is. Record these, and them multiply them by each other in order to find the speed of the wave. Do the same for all of the mediums.

3. Analyze – does the wavelength, frequency, or speed change according to their flexibility?

IV. RECORD & ANALYZE

DATA:

LONG SLINKY:
Wavelength: 75 cm (20 cm to 80 cm)
Frequency: 3 waves per second
Speed: 225 cm/s
BIG SLINKY:
Wavelength: 320 cm
Frequency: 2 waves per second
Speed 640 cm/s
BIG ROPE:
Wavelength: 102 cm
Frequency: 2 waves per second
Speed: 204 cm/s
YELLOW PIPE:
Wavelength: 98 cm
Frequency: 1 wave per second
Speed: 98 cm/s

Analysis of Data: What happened? Do you see any
patterns? Do you believe that your data
shows accuracy and precision?
The flexibility of the medium doesn’t really seem to affect the wavelength at all. The long slinky has a really small wavelength, but the big slinky has a really big wavelength. This may have some relation to the frequency, which does seem to follow a pattern. However, it may be just a coincidence that the frequency follows a pattern according to the flexibility, so if I were doing a more detailed lab I would test out each material several times and find the average, to make sure that it’s not a coincidence that the more flexible, the more frequent the waves are. I think that because the wavelength didn’t depend on the flexibility, which means that the speed doesn’t really depend on the flexibility either (because wavelength and frequency are both factors of the speed). And, because of that, the amplitude doesn’t end up depending on the flexibility. The only thing that does is the frequency!

IV. Concept Acquisition (CONCLUSION): State the guiding question.
Present the relevant experimental results. Discuss the
relationship between variables. What can you conclude?
Was your prediction correct? If yes, explain. If no,
explain what you understand now about this investigation
and how it taught you something new.

The guiding question was “does the flexibility of the medium affect the amplitude of the wave?” I think that this lab was a very interesting one to do because the amplitude of the wave can include a lot of things. It basically just describes however a medium is disturbed. The wavelength and the frequency multiplied by each other equal the speed, and all three of those factors combined describe the amplitude. It’s interesting to see how if you change just one variable (in this case, the flexibility), then the whole answer changes. My prediction actually wasn’t that specific to the question – I just described the amplitude in general and the results showed that it was really different for each thing describing the amplitude – the wavelength, the frequency, and the speed.

V. Concept Application (FURTHER INQUIRY): Examine the validity of
your data and infer what you think the major causes of
error may have been. Propose methods of improvement. For
example, what modifications did you need to make or would
make next time? Whatever happens in a test, think about all
the reasons for your results. Sometimes this thinking
leads to a new hypothesis. Write down these new hypotheses
(predictions) or inquiries (questions) you may have here in
this section.

What I would want to do if I were to continue this lab is that I would want to try each factor as the manipulating variable – change the wavelength, but not change anything else. Change the medium, but not change anything else, and so on. I think that what could have been improved were the measurements – I’m not sure that they were correct, because some of the data doesn’t really make that much sense to me. If I had tried it a couple of times and then found the average, it would have probably have made for a better analysis.

Letter to Sony Ericsson

The packaging company that I chose was Sony Ericsson because it was the company that made the most unnecessary packaging that I had in the house. Before I wrote my letter to the company, I researched a little on what they are doing currently, because the package I took was from 3 years ago. It turns out that they have improved a lot since then. Now they have a very eco-friendly model of a cell phone. Otherwise known as Cedar, it is a cell phone that has been created from recycled plastic with a low power consumption charger. It's available in a compact box with the manual in an electronic form. This is essentially the exact opposite from what it had 3 years ago. The model that I had was two boxes, a carton, a bunch of plastic bunched up, and a bunch of different papers stapled together with the instructions.
Essentially, what I wrote to them was that I was glad that they had decided to make a more eco-friendly cell phone, because not only was it a good decision for the environment but also for their profits. It appeals to people when it's completely environmentally friendly.

Ultimate Survival Unit Reflection

Reflect on what has helped you in understanding the "big idea" of the unit.
(Big Idea: Students will understand the use and management of natural resources, the transformation of resources into human capital, goods, tools and machines as well as sustainable development of human society to maintain the delicate balance between man and the natural environment.)

What has helped me understand the "big idea" of the unit is a couple of different things. First of all, seeing everyone's presentations on the world's environmental problems helped explain a lot about the different aspects of global warming, of endangered species, and other problems. Also, watching the video really explained a lot of things. They were my favorite parts of this unit because although they were very explanatory, Food inc. and the overfishing movie made me think a lot about what exactly we're doing to this earth. It's sad to see the way we now know what we're doing, but plenty of people don't even try to stop it. I think in order for our environment to be properly saved, we need to work together as a world, not just a country or city. If just one country decides not to follow any of the measures that are there to help stop global warming or something then that already poses a huge problem, let alone if all countries except for a couple do that (which is the situation we are in now). Some main adaptations include camouflage, swelling up to double size, bright colors, fake patterns, hiding, fake smells, strange sounds, etc.

Reflect on the unit question (What is a necessity and how does an organism ensure survival of its species within its environment?) and how it relates to the unit title: Ultimate Survival.
The unit question is really what the whole thing is about! An organism requires adaptations, and useful ones, in order to survive in a certain environment. Species fight to the death just to be one of the ones that ends up surviving. Hence, the ultimate survival. Species can fight for survival, but even with the fight, eventually those species that don't have the right adaptations for the environment will be influenced by natural selection. A necessity is something that a species must have to survive. A species needs to be able to reproduce, needs to be able to excrete waste, needs a source of energy such as water, food, or sunlight. An organism is only able to survive if it has those things.

How did the unit question allow us to view survival through The Area of Interaction: Environments:(FOR EXAMPLE: The effects of one environment on another, the roles our environments play in the lives and well-being of humankind, and the effects of our actions, attitudes and constructs, such as sustainable development and conservation.)

We, as humans, have started to get used to using way too many resources, because we think that we have that luxury. Well, people starving on the streets is bad, but the reality is that just the pure fact that some people take too much of the earth and some people take too little is what helps the earth survive! The fact is, that if everybody lived like even the average person, we would need a lot more than what we have to sustain us. We took that quiz in science class, and I got 2.9, which isn’t wonderful, but better than what some people got. This tells me that people need to start to realize what they are doing. We are killing off animals for more money than we need, we are eating massed-produced meat that we know about and LIKE, and we are creating air that isn’t satisfactory for breathing much longer. For the past 20 years, we have messed up our habitat subconsciously, and now we don’t know how to fix it.

What would you have liked to do more of? Less of?
I would have liked to see more of that Overfishing movie, because it was not only very interesting and informative, but it was also very moving. Otherwise, I actually really liked this unit. Before it I knew about global warming and everything, but I didn’t really realize the magnitude of our earth’s problem. About what actually happens to all the trash that we have thrown away, about how money-hungry people can get – they want to be billionaires on the expense of literally everyone’s life, including theirs! About how all we have to do is press a button and thousands of poor creatures get killed, many of them not needed at all. About how we’ve cut down so many trees for tables and other furniture that it’s getting hard to breath, and about how at the expense of our atmosphere we have been using daily materials at twice the normal rate – just because companies make it easy.

There isn’t really anything that I wanted to do less of – I thought the unit was pretty straightforward and interesting – first we learned about how animals survive without us, and then we learned about the effect of us on the environment.

In your point of view, how well did we investigate the unit question, concept, and area of interaction? Include this in your reflection as well and give specific examples to support your opinions.

I think we investigated the unit question and concept really well – they explained so much in suck simple words, and they made me understand just how serious everything that we have been thinking was a joke is. I liked how first we learned about the things that we’ve been learning since 1^st grade, but at a different angle. I also liked how we didn’t take as many notes this unit and did more interactive projects than usual. It was a good twist. I thought it was a really good idea to have the project of different environmental situations, because it taught me a lot and I actually enjoyed researching and coming up with a presentation for it. And then, my favorite – the videos at the end were great and, although they scared me, now make me see every little thing I do as something against the environment. They were a really great way to raise awareness.

Reflection - Green Plastics

How are these plastics being developed?
Green plastics are developed by taking chains on polyactic acid which join and make polyactic acid oligmers, then, due to a chemical reaction become lactide which then become the most manufactured type of green plastic, or PLA.
What makes these plastics green?
What makes plastics green is whatever substances they come from. They usually come from corn, sugar beet, and sugar corn. Those ones are biodegradable and natural, or in other words, green.
What where some of the issues mentioned with the packaging?
A problem that we could face is we could start using so much of those crops for plastic and then end up not having enough food. As well as that, while growing the crops we could end up using too much land. Also, because growing corn efficiently requires pesticides, we use oil and gas to use trucks which then emits carbon dioxide. Finally, a problem with these green plastics is that when they biodegrade and then give off methane.
How might these green plastics change packaging practices?
This packaging, although not perfect, could change our world a lot. It is very eco-friendly and could be very helpful so that there is not so much waste in the world. It might even help make there be less need for recycling!