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!

Current Events: Endangered Parrot!

Link: http://news.discovery.com/animals/endangered-parrot-identified-in-australia.html

Author: Tim Wall

A new species of endangered parrot was recently discovered! The western ground parrot split off from the eastern variety (the one familiar to scientists) about two million years ago, according to evidence. Scientists already knew about the western ground parrot's existence, but didn't realize the western and eastern varieties were different enough to be separate species, even considering that the species live on opposite ends of Australia. The scientists looked at DNA preserved in museum collections, and they found that there was more than a 5 percent variation in the DNA. Only 110 of these birds exist currently! They live essentially all in one park, so if a wildfire or some other accident occurs, then two species are wiped out at once. This could be very dangerous for the food chain and the environment of Australia, so it is important that these two species of parrot be kept safe.

I found this article to be very alarming, although also very interesting. I was surprised that scientists didn't know about these two different species before! If they did, it may have helped stop the birds from becoming endangered in the first place. What the article didn't tell me is why the species split in the first place. I would like to find out why this happened, because I think that if scientists knew why this happened they could also ensure the safety of several other endangered species!

Food Inc. Reflection

After watching Food Inc, what are your impressions of how science of food industry, technology of food industry, and society are interrelated?

This movie caused me to go a bit sick in the stomach. Afterward, when I ate a pepperoni pizza, I couldn't stop thinking about how they treated the pigs on the different farms. I think it's terrible, and there should be something that we can do about it, but frankly, we need our food. And the people who make our food aren't really the ones to blame for our obsession with deep-fried meat! We've kind of created a trap that it is impossible to get out of, because if we change the way we make food, then we change the food, and we don't even get the same amount anyway. The whole food industry relies on consumers, which is how society affects the food industry. It is a very tricky business, because if the food industry markets one thing wrong, then the whole thing that has been balanced out so carefully falls apart.

How did the film describe science & technology as a positive or negative impact on society or the environment?
The film described science and technology as more of a negative thing, because it showed how people take science and technology to create a lot more order and machine-made things. Instead of using science and technology to make things more earth-friendly, the food industry has used science and technology to mass-produce more food, to kill off animals in an orderly fashion.

How do our consumer choices affect what is out on the market and therefore, our own species survival? Basically, a total of about 5 companies own the whole food industry. If one of those goes out of business or does something weird to our food, we are in big trouble. If we all decide to stop buying meat from a particular company, we lose a LOT of food.This makes our survival very difficult, because then many people don't have enough food,and people do need their meat!

How are we as humans connected to how the Earth is used? We influence the Earth very directly, in fact. Every time that we pollute, we cause more damage. The Earth is what we made it with machines and factories, with more complicated packaging, with flashy ads and mass-production. We have gotten rid of many species of animals because of how greedy we were, and it is up to us whether the Earth will survive for much longer or not!

When do we say "no" to more high tech devices and go back to what caused the problem in the first place? Why are we only into the "HOW" things work and not the "WHY" things don't? What did this farmer mean? Very often, people don't say no to more high tech devices and just decide to try and figure out more ways of doing things. However, I think that when it originally doesn't work, then it's time to go back and figure out something else, not to try and prove that the first thing is always right by building on it. Often this causes more damage than good.

What is the difference between natural farming and industrial farming? Which is better? Are they both necessary for human survival? Why or why not? Natural farming is much better than industrial farming. Natural farmers actually care for their animals, or better than industrial farmers. Very often, industrial farmers do very cruel things to the animals without caring about them at all. For example, they would feed cows corn even though they can't digest it. This is only because corn is really cheap and easy to grow! Natural farmers, however, normally feed cows what they would eat anyway - grass! One could say that they are both necessary for human survival, but this is only because we need so much food in order to survive and the only way to produce food that fast is by industrial farming. It just seems so cruel to subject the animals to such bad treatment, and I wish it would be possible to know whether I was eating food made from natural farming or from industrial farming.

If technology and industry have improved so much that we are getting faster, fatter, bigger, and cheaper, how are science and technology held responsible for improving or ruining human health and survival?
Well since we have about 5 companies that control our survival, we are pretty much cornered. Science and technology could be very helpful, but only if companies use it the right way. If companies could find a way to use science and technology for a way to make things more efficient AND better for animals, then a lot of our problems would be solved, or minimized, anyway.

What economic costs, environmental costs, ethical costs, health costs, and cultural costs did you observe while watching the film? The companies from the movie attempted to find the cheapest way to do things, and this is all right, but the problem is the health of not only the animals, but also the people who eat the animals! As mentioned before, because the cows aren't physically able to digest corn, E. coli breaks out. The companies keep feeding the cows corn, because it's the easiest and cheapest thing to feed them, and then they make a hole in the cow's stomach and take the corn right out. This is one way it affects the health of animals.
Finding the cheapest way to do things also often affects the health of people, too! Because of the E. coli, one kid died from just eating a hamburger in 12 days. This is very bad for our population and there should be something done to prevent this type of thing in the future.

Finally, state your final thoughts about this film and any changes you see happening in the food industry in the future or even your own eating habits.

I am not able to look at food the same way anymore, ever. Whenever I look at the beef in a salad that my mom makes, I can't stop thinking about the cows being killed in the factories and being gutted without any concern for the poor creatures. I think it is necessary that the food industry has someone step up to help them come up with a solution for all those problems. Also, I think that the government should fix up its weak spots so that companies like Monsanto don't end up getting so much power.

Bats Crash When they use Their Eyes!

Link: http://news.nationalgeographic.com/news/2010/11/101115-bats-vision-science-animals/

Author: Rachel Kaufman

New research says that being a blind bat has its good sides - in fact, when wild bats use their vision to fly they are more likely to crash! Bats normally navigate by sending out sound waves and listen to echoes bouncing off their prey. They are also able to navigate visually, but the vision gets worse the brighter it gets. Scientists tested this by setting up an obstacle course in Ontario. They used 3 different light conditions - dark, dim, and bright. The results showed that the vision caused them to crash, but the bats still chose to use it in the well-illuminated course.

I thought this article was very interesting because although I knew that bats used their hearing for navigation, I never knew that they were actually able to see. I thought they used their hearing because they had terrible vision or something. This is yet another example of how animals use adaptations to help them survive and find prey. It is also probably what makes bats such great hunters.

Analysis of Owl Prey

Birds = 9.1 %
Shrew = 1 %
Mouse = 19.5 %
Vole = 30.1 %
Rat = 40 %







Questions:
1. Based upon the class data, rank the most frequently consumed prey for the class "owl population".
The most frequently consumed prey for the class "owl population" is the rat, followed by the vole. Next comes the mouse, then the bird, and finally, with only 1 % of the owls' diets, the shrew. The owl population did not consume any insects.
2. A predator expends energy when hunting for food. Which is the more "energy expensive" cuisine, 35 insects at 1 g each or one 35 g vole?
The more "energy expensive" cuisine would be dining on 35 insects, because it would take more time and more energy to capture them whereas it would take less time to catch the vole.
3. Based upon your data, suppose the shrew population seriously declined. Would it affect the areas owl population?
It would not drastically affect the owl population because the shrew only makes up a small part of the owls' diets. However, if the population of, for example, rats declined, then the whole area would be in big trouble because the rats make up so much of the owls' diets and rats are also common prey for other animals.

Current Events #6 - T. rex's big tail - key to survival!

Link: http://www.biologynews.net/archives/2010/11/15/t_rexs_big_tail_was_its_key_to_speed_and_hunting_prowess.html
Author: Biology News Net

When we hear "T. rex", we think of a huge monstrous dinosaur with a pointlessly big head and big tail. However, extensive research shows that powerful tail muscles made the giant dinosaur one of the fastest moving hunters of its time. The paleontology student researching this, Scott Persons, began his research by comparing the tales of reptiles such as crocodiles and Komodo dragons to the T. rex's tail. He realized that for all of the animals he had been researching, the biggest muscles were attached to upper leg bones. The muscles are called "caudofemoralis muscles" and provide the power stroke which may have been a key thing in the T. rex's quick movements. However, there is a distinctive difference between other reptiles/animal's bones. The tails of both T.rex and modern animals are given their shape and strength by rib bones attached to the vertebrae. Persons found that the ribs in the tail of T. rex are located much higher on the tail. That leaves much more room along the lower end of the tail for the caudofemoralis muscles to bulk-up and expand. Without rib bones to limit the size of the caudofemoralis muscles, they became a robust power-plant enabling T.rex to run.
This article was interesting to me because I haven't really learned about dinosaurs in the past but I wanted to know a little more about them. I think it's really cool how scientists are able to take a skeleton and compare it to things alive today - it really shows how science has advanced over the past few centuries. The article also helped me understand a bit more about how there are animals that are made to fit each environment and thrive in it, such as the T. rex, and there are animals that may not do so well. This is just a simple concept in each ecosystem - natural selection.