Make an Impact!

Make an Impact! :)

Guiding Question:

What are the factors that affect the appearance of impact craters?

Hypothesis:
If the speed of the falling object (meteor) is bigger, then it will create a bigger crater.

Materials:
Safety goggles, tray, flour, (soil and corn meal-optional), notebook, spoon, small and large marbles, ruler (cm), Excel and word.



Data Info:

The following data table contains data that we obtained during this experiment; using a marble as an impactor. In the table, data for different heights of drops in three trials are presented.






The graphs below the table are constructed using the average crater diameter and average depth of the crater.






Data Analysis:

My hypothesis about the appearance and size of the crater are supported by the data that we got through this experiment. My hypothesis was that If the speed of the falling object (meteor) is bigger, then it will create a bigger crater. In this case, the velocity of the falling object is certainly connected with distance in which that object travels, so the higher the distance of dropping, the bigger the speed of hitting the flower surface will be. That means that the bigger the velocity, the bigger the impact will be, and the bigger the crater will be created.
From the data presented in both the table and the two graphs, we can see that with the increase of drop height, both the diameter and the depth of the crater will increase too.


Conclusion:

We can conclude that if the marble is dropped from a higher distance, it will produce a much bigger (both wider and deeper) crater. We have proved that by the data shown in the data table- and that has approved my hypothesis that the velocity of hitting is one of the important impacts that affect the crater appearance.



Further Inquiry:

For the further inquiry, I believe that we should think about all the factors that affect the crater formation such as velocity of the impactor, its size, its weight (that means from which material the impactor is made) etc…. All of these are factors that we could test in some further research by, for example, using marbles made of glass and sponge, or using bigger and smaller marbles made out of the same material and dropped from the same distance.

Current Event 9

Super Storm on Saturn
Paul Walsh
http://www.astromart.com/news/news.asp?news_id=1184
5/19/2011 10:47 pm

This article talks about a super-duper huge storm which has unexpectedly occurred in Saturn’s northern hemisphere. This violent storm has started out like a simple disturbance that occurred as an early spring storm, but soon it exceeded the limits and appeared like a precursor for disaster of hot gas plumes that tend to destroy Saturn’s stratosphere. The storm has rapidly increased to about a 5,000 kilometers wide thunderstorm vortex. Scientists say that the storm like this is pretty rare-this is the sixth storm recorded since the first one found in 1876, and the last one happened in 1990. However, this is the first major storm observed by an orbiting spacecraft and studied with the thermal infrared wavelenghts, which means that the scientists have much more data to analyze and to prove the collosal force of this storm. The data from infrared observations are the key point for the researcers-they show them a lot of things like; what are the conditions inside the storm including temperature, winds and atmospheric composition of gasses. This data has showed that huge amounts of matter and energy had been transported around Saturn by this storm and that this has interrupted the planet’s weather pattern conditions.

The most surprising thing was that something that has started like an ordinary disturbance in the planet’s hemisphere has spread to unexpected limits threatening to seriously disturb Saturn’s higher layer of the atmosphere called stratosphere. A Stratosphere is part of the sky where commercial planes fly in order to avoid turbulences, so, I wouldn’t like to be in that Saturn plane . Another thing that has worried me while reading this article is that THIS SIMPLE DISTURBANCE HAS OVERGROWN IN AN INCONCEIVABLE STORM that tends to disturb wheather pattern on Saturn, and who knows which other doubt exists!!!

Reasons for the Seasons

In our science class we did a very interesting lab that has clarified me a few things about the season creation on Earth. In our lab, we used a styrofoam ball as a model of the Earth, and we used a flashlight to light our model Earth (who's axis was tilted about 20 degrees) and we have observed what is happening in many different cases. After the lab, we were supposed to answer these questions. So here they are:

1. When it is winter in the Northern Hemisphere, which areas on Earth get the most concentrated light? Which areas get the most concentrated light when it is summer in the Northern Hemisphere?
When it is winter in the Northern Hemisphere, the most concentrated light is in the Southern Hemisphere, and when it is summer in the Northern Hemisphere, then it gets the most concentrated light (at that moment, it is winter in the southern hemisphere).

2. Compare your observations of how the light hits the area halfway between the equator and the North Pole during winter and during summer.
During the experiment, we observed that during winter, light doesn't hit that middle area very much. Light hits the areas closest to the equator-because of the shape of the Earth. When we did our experiment with the acetate grid, we saw that the squares from the acetate grid on the northern hemisphere looked like rectangles. while when they were closest to the equator they were perfect squares. This means that the light was less concentrated at the poles than the areas close to the equator.

3. If the squares projected on the ball from the acetate become larger, what can you infer about the amount of heat distributed in each square?
When the projected squares become larger, it means that less heat is found in each square because the light energy is spreading out through a bigger surface area.

4. According to your observations, which areas on Earth are consistently coolest? Which areas are consistently warmest? Why?
The consistently coolest areas are the North and the South Poles, because only small amounts of sunlight come in those areas, and we can say that they are never directly illuminated. The warmest area is in the equator because it is in the middle of the Earth and it is always directly exposed to the sun.

5. What time of year will the toothpick's shadow be longest? When will the shadow be shortest?
The toothpick’s shadow will be longest during summer, because it is closer to the sun and the light is directly shining on it. But, in the winter, the shadow is shortest because there is a bigger angle of the light that hits it.

6. How are the amounts of heat and light received in a square related to the angle of the sun's rays?
The amounts of heat and light received in a square are biggest when the light directly hits the surface, so this angle is almost zero while when this angle increases, (because of the tilt of the Earth and Earth’s round shape) the square becomes rectangular and this light energy is spread through these rectangles.

7. Use your observations of an Earth-sun model to write an explanation of what causes the seasons.
The seasons on Earth are caused by the Earth’s round shape and the tilt of Earth’s axis from the normal position, to the line connecting the sun and the Earth. This tilt influences the way that sunlight hits the Earth’s surface- the more direct the sunlight hits the Earth, the warmer it will be. While when there is a bigger angle of sunlight toward the surface, it will be cooler.

Phases of the Moon

What do you think about when you see the moon's 'shapes' changing? Do you think that there are many moons changing everyday, or do you think you are just seeing one moon change? What causes the moon to change, and what are these changes called? They are called the moon's phases. They appear because the moon is orbiting around the Earth, leading us to think that there is more than one moon. The shape of the moon varies from a full moon (which is when the Earth is between the sun and the moon) to a new moon (which is the moon being between the sun and the Earth).

When we look at the moon and we only see half of its surface, which is the side that is facing us. We can observe that as the moon orbits our Earth, the side of the moon, which is facing us is full of light (illuminated) by the sunlight. So when we look at the moon, sometimes we see some parts that are light (by the sun) and some parts that are shadowed. For example, if you have a look at the First Quarter moon, half of it is a shadow and the other half is light (which comes from the sun). We can see only part of it which is illuminated by the sun. This means that if the moon is between the Earth and the Sun, we won't see it because there is no illumination from its surface that can be seen the Earth's surface. As the angle between Earth sun axes changes, the appearance of the moon will change too. So, in a moment we will see it as a full moon, and that happens when the Earth is between the Moon and the Sun, so the whole "Half-Ball" of the moon is illuminated. When I was small, I used to ask myself- why would somebody cut moon energy weight?! :)

Phases of the moon Reflection

In science class, we explored a variety of things about the phases of the moon. We did a lab, we did an activity (creating a moon clock) we read a section in our textbook, and we looked at a simulation of the moon phases and how they work.

My favorite activity was creating a moon clock- because it helped me understand the moon better. Our teacher had us record when each phase rose at which time. I noticed that when the moon is at noon, we don't actually see it, so it becomes a new moon. At sunset, we see a First Quarter, and at midnight, we see a Full Moon. Finally, at sunrise we see a Third Quarter (Last Quarter). Also, when the sun is on one side, the moon has a lot of light from that side, however, we as people see it differently because it orbits around the Earth. A lunar month is the amount of time it takes for the moon to pass through each of its phases. A lunar month takes a;proximately 30 days to reach the next new moon from the starting new moon- and this is called a Synodic month.

Tuning Fork Lab

TUNING FORK LAB

Guiding Question: How does density of various solids affect the way the sound waves travel from the tuning fork?

Hypothesis: If the material is denser, then the sound from the tuning fork will travel faster (higher frequency) and it will be much louder.

Materials:
1. Tuning fork (the main resource)
2. White board (plastic)

3. Table (wood)
4. Locker (metal)

5. Piece of Paper (paper material)

6. Rock material
7. Watch stop

8. Computer (for putting and processing the data)

Procedure:
1. Take a pencil and a notebook before you get started with your experiment, because you wouldn’t want to miss something out!
2. Draw a table in your notebook with all necessary columns and rows (this table should contain the type of material, its density, time of vibrations and observations, and all that for different types of material)

3. Take a tuning fork of normal size and hit it on chosen material. You should feel the vibration of the tuning fork while you’re holding it.
4. Get a timer/watch stop and time how long the tuning fork vibrates.

5. Record your observations in the table in the notebook.
6. Repeat the steps 3-5 as many times as you have materials.

Record and Analysis:

The measurements with the observations are given in the table below.

Material	Density, kg/m3	Time, seconds	Observation
Metal (Locker)	7400-8000	About 25	Soft vibration, long lasting
Plastic (White Board)	900-1100	About 19	Loud but slow
Wood (Table)	700-850	16	Quiet and slow
Rock	2000	About 22	Vibrates slowly but is loud.
Paper	21450	12	Low pitched

Conclusion:
Jovana’s conclusion:
In conclusion, I can say that Ergi and my hypothesis was partially wrong because the vibrations for the denser materials were long lasting, but soft, so I can’t really say it was faster, as I suppose. The pitch was lower for denser materials, but the sound was much louder. This means that only part of our hypothesis was true.

Ergi’s Conclusion:
In conclusion, our hypothesize was right. If the material is denser the tuning fork will be slower. On the table above hard materials all ways lasts longer and has a heavier sound than the others.

Further Inquiry
Jovana’s Further Inquiry:

In the future, we can improve our experiment by doing at least three trials with each type of material and recording each time of vibrations as well as observations during these vibrations. We could also use different types of tuning forks and compare them. And, to conclude, I’m not sure if the densities for the materials are exact because I took them from the internet, but, there are different types of plastic or metal etc.

Ergi’s Further Inquiry:
An interesting thing I learned was that on wood it makes a very long vibration and it lasts for a long time. But, the song is not that high.

Waves Unit Reflection

How does the use and study of waves affect societal well-being?

As I learned throughout this unit, there are a lot of ways that waves and their use might affect societal well-being. Firstly, waves are all around us – so, how can’t they affect something? We can summarize and say that they help us a lot-how would we be able to help humans from death and diseases without UV rays (new born babies in hospitals), x-rays or gamma rays (used in hospitals to treat cancer). Doctors use magnetic resonance and radio waves to see a picture of human’s tissue…. Radio waves and the Doppler effect are used to find the speeds of moving vehicles and of moving balls at sport events such as tennis matches- we wouldn’t want anyone to cheat on a tennis match, would we?! It’s impossible to live without the electromagnetic spectrum. Waves help us to understand the noise from loud music, they describe how instruments work, and certainly how glass can break during loud music (resonance). If we put all of these things together, we’d realize that all of these small things happen to us in our everyday lives, and we don’t even realize it! It seems that there is no way in the modern society that people can survive without waves… But we need to be careful!!! Too much of everything can be harmful to everything and that the same with waves- I can remind on hearing loss from too loud music, brain cancer from too much talk on mobile skin cancer from too much UV exposure….

I have learned a lot throughout this unit about different types of waves starting from water waves, to many extraordinary light waves, radio waves, microwaves etc.
In the beginning of the unit I thought that waves were just a bunch of waves we see every day at the beach, and I thought that only water waves existed (which is sort of embarrassing to admit). But now I know a lot more about waves that I never really knew I’d learn. There is a big difference between all of them, starting from ‘simple’, visible water waves, to seismic and sound waves, and ending with the electromagnetic spectrum (radio, microwave, infrared, visible light, ultraviolet, x-rays, gamma rays)
I mostly liked learning about the electromagnetic spectrum because it’s something I have never heard of before, and it really taught me a lesson. I learned a lot of facts, especially about microwaves because I had to make a Powerpoint about it with a group. I learned that you can get cancer from talking on the phone for a long time (especially little kids, because their brain is still developing). Listening to other classmates’ presentations, I learned a lot of valuable facts and included them in the debate discussion we had in science class. For example, I learned that visible light waves are the only electromagnetic waves we can see, and that we can see these waves as the colors of the rainbow. I have also learned that gamma waves have the smallest wavelengths and the most energy of any other wave in the electromagnetic spectrum. Pretty interesting, huh? I used to think that x-rays were only types of ‘machines’ used to make our eyes think that we’re seeing a skeleton body. But now I know that x-rays are a lot more than that. They have smaller wavelengths and therefore higher energy than ultraviolet waves. I would not go too deep into x-rays, because I could talk about them for hours. All of these things we learned in class are amazing, I would not never have learnt this if it weren’t for our fantastic teacher, Mrs.M! I would not really change much for next year’s grade 7 students- I loved the debate we had, it made me think deeper about the electromagnetic spectrum, and I think the presentations we did in groups were really useful too. However, I would make a little difference. In my opinion, next year you can have more students presentations of each part of the electromagnetic spectrum- so each of us would learn a whole bunch of the information they have researched about. This way, the grade sevens would learn a lot of if different interesting facts about waves but seen from the other students point of view!

Food Irradiation

FOOD IRRADIATION

Step One:
During science class, we were talking about food irradiation. We were each assigned to research about this topic. Since Riena and I sat next to each other, we decided to be partners and talk about the cons of food irradiation, while Maria and Emily who sat at the same table decided to research about the pros of food irradiation. Once that was done, all four of us gathered up and started doing a debate. We surely used our research notes to help us during the debate.

Step Two:
There are a variety of problems with food irradiation. It kills the microorganisms that make the food less healthy but, at the same time, food irradiation destroys nutrients such as vitamin A, B-1, E and K. It takes away approximately 10 percent of health away and leaves 90%. Even by putting your fruits and vegetables in the refrigerator can lead to small losses in nutrition-this also goes for cooking too (it can make it lose some vitamins). Irradiation of food may change the molecular structure of the food which can create bad chemicals such as benzene and formaldehyde, and intaking a long term of these chemicals can lead to cancer or other disease-but also other ways for preserving foods, such as spraying with pesticides, are proven to be much more harmful for human health than irradiation!

Step Three:

Some pros of Food Irradiation that I heard from the other team were:

- Kills pesticides, bacteria and insects

- It doesn’t kill more nutrients than a conventional oven does

- Can allowed for food to be stored longer

- Radiation kills up to 90-99% of dangerous bacteria in the food.

- It is good for the environment

The cons Riena and I discussed:

- The levels that are allowed to be used do not kill the viruses

- Can only be used on a limited number of foods.

- Approve irradiation in food as flawed

- Accidents by people handling radioactive material is possible

- Does not kill all the bacteria and the bacteria that is not destroyed supposedly comes back stronger and even harder to kill

Step Four:

If I am seeing two containers in the super market (one is irradiated and the other is not) and I have to choose which one to pick, I would say that it depends on which type of food I would buy. If I’m buying strawberries from Serbia that are fully grown in the spring season in Serbia where there is no need for preserving, I would buy the non-irradiated strawberries. But if I’m buying bananas from South Africa, then I would surely choose the irradiated food because of the reasons I previously mentioned.

After our debate, we have concluded that irradiation of food is something that certainly doesn’t need to be forbidden but it is not necessary to be done with all types of foods. I believe that science did a good job by irradiating food because it’s a much healthier way for preserving food than by using other chemicals instead.

My thinking about food irradiation has changed quite a lot. Earlier I thought that the irradiation of food is a bad thing that can really harm both food and human health. While listening to Maria and Emily, I wanted to be on both sides because I couldn’t decide what’s better. Now I think that irradiation of food is really good when it is actually necessary and if it properly applied. I enjoyed the debate because I thought it was a really good idea to lead us to think further more about the irradiation of food. I really hope we discuss about the pros and cons of the future topics we will do in science class.

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