Wave and Ball Barrier Interaction Lab

Guiding Question:

What happens to a wave as it hits a surface it cannot pass through?
Once a wave hits an object it can't go through, i just bounces back, making a pattern between the waves where they just cross over each other. I made several tests where i saw that the wave made an interesting pattern when it bounced back from the barrier. Once the wave hits the barrier and starts bouncing back, some of the energy of the wave starts decreasing, because of the pressure against the barrier. When a wave meets a barrier and it reflects off the surface of the barrier, some, or most of the waves energy is lost, because of the pressure that is being made against the surface of the barrier. When a wave finds a hole in a barrier, and manages to pass through, it either bends or spreads out, This is called diffraction. Another thing I saw, was that the interference between two waves or more happens, they affect each other.

Does energy (density of the ball) affect the wave’s path?

In my mini lab I noticed that the density of the ball does affect the wave’s path. I used three different types of balls: a medium sized bouncy ball, a light Styrofoam ball, and a small orange light plastic ball. In the experiment the Styrofoam ball and the small orange plastic ball were both every light, the rubber bouncy ball was the heaviest. When I tested the bouncy ball I found that it made the widest triangle when bouncing off the wall.The bouncy ball had the biggest angle of incidence, and angle of reflection.The foam ball made the second biggest triangle when reflecting off of the wall. It had the second biggest angle of incidence and angle of reflection. The small light orange plastic ball made the smallest triangle when we were testing. The small light orange ball had the smallest angle of incidence and angle of reflection. I suppose that this was the lightest or the least dense ball that I had. I noticed that when the ball hit the wall refraction occurred, when it hit the wall the balls slowed down.

How is the angle at which the ball (wave) hit the wall related to the angle at which it bounces back?
As I found in my testing my lab I found that the angle at which the ball hits the wall it comes back at about the same angle. When testing the lab 10 times each one of my results ended up to be the lightest and least dense the ball the smaller the triangle the ball would make after the ball reflected the barrier or the wall. I did a little experimenting with the angles I rolled the wall and found that it would reflect off the wall about the same place every time. I noticed that the incoming "wave" reflected off the wall at the same angle. This is because the law of reflection states that the angle of reflection equals the angle of incidence. To conclude this lab, I would like to say that it was a very interesting and inventive was to learn how waves reflect of a barrier.

Tsunami Essay

Roy Elal 7B Due Date: 2/25/11

What is a tsunami? A tsunami is a very large water wave that is caused by an underwater earthquake or volcanic eruption and often causes extreme destruction when it strikes land. Tsunamis can have heights of up to 30 m. and reach speeds of 950 km. per hour. They are characterized by long wavelengths of up to 200 km. and long periods, usually between 10 and 60 minutes. How are tsunamis caused? There are a couple of ways, and I will mention three. The first way, and the main way, is by underwater earthquakes, usually these types of tsunamis cause the most damage. Another reason is by volcanic eruptions, which is a rare and an infrequent way, which also causes a lot of damage, to the land nearby. The last way is by extraterrestrial collision, also known as meteors, or asteroids, are the most unlikely ways for a tsunami to occur. I live in Belgrade, and in Belgrade, it's almost impossible, for a tsunami to because, there isn't enough water, or sea, for a tsunami to happen, unless a tsunami happens from ada ciganlija, and I doubt that would do a lot of damage. Tsunami have no positive effects, on neither people, or the Earth. Many of the tsunami witnesses say tsunamis sound like 'freight trains'.

Safety in a tsunami

• Go to a higher ground immediately (recommended by foot.)
• If not possible to go on high ground, then go inland as far as possible.
• Have a radio, to receive information about the tsunami.
• Most importantly, don't panic!

Ring of fire

The Ring of Fire, or the Pacific Ring of Fire, is a 40,000 km (25,000 mi) stretch of geologically active land extending in a horseshoe shape around the Pacific Rim. The Ring of Fire gets its name from the numerous volcanoes and earthquakes along it — 542 volcanoes and thousands of minor earthquakes every year. The Ring of Fire is the most volcanically active area on Earth: 50% of the world's active and dormant volcanoes can be found here, 90% of the world's earthquakes, and 81% of the world's major earthquakes.

Tsunami impacts

Tsunamis will definitely cause casualties and injuries. Tsunamis, as they originate from the sea, will wash fishing boats and other boats such as cruises onto shore. The boats will be stuck on shore and usually wrecked from the forces of the wave. The waves will also cause fishes to be washed onto shore and stuck there to die. They can also flood the lands near the shore, causing people to die from them. This will damage the crops and cause nearby buildings to collapse. Some people might be trapped under the buildings and die. They uproot trees too, causing them to fall on houses and people. Lastly, they cause economic decline as they have to spend a lot of money rebuilding the houses and restoring the original landscape, especially if it is a beautiful resort. They would also have to compensate the victims' families as a form of comfortation. They would also face a decrease in tourism.

Tsunamis are considered one of the most deadly natural disasters that occur especially if you live on the coastline. In total, Tsunamis killed above 420,000 people, and some of the bodies of those people have not been found yet. These vicious, shocking waves do not only kill, and injure people and animals, but they also destroy, and just demolish buildings, and in the end, the country might need billions of dollars to repair everything, which is usually a problem in small or poor countries. For example, in 2004, a terrible tsunami occurred in the Indian Ocean, and the force of the tsunami was like the force of the 23,000 atomic bombs that were dropped by the Americans on Hiroshima, Japan, during World War II. This tsunami killed 150,000 people, and left millions homeless, in the 11 countries it affected.

All-in-all, as you can see, tsunamis can be very dangerous! So if you are going on a vacation, make sure the place you want to go doesn't have tsunamis often! Mainly around the Indian ocean. Unfortunately, there is never a 100% way to predict a tsunami, only very close to that, just like no one can predict (almost) anything for 100%.

Interesting facts

• If the ocean is deep, tsunami's can be less than a foot high on the ocean's surface.
• Scientists can accurately estimate the time when a tsunami will arrive almost anywhere around the world based on calculations using the depth of the water, distances from one place to another, and the time that the earthquake or other event occurred.
• Hawaii gets a tsunami, once a year, and a damaging tsunami, once every seven years.
• In 2004, the Indian Ocean tsunami was caused by an earthquake that is thought to have had the energy of 23,000 atomic bombs.

Bibliography

Burande, Abhay. "Tsunami Facts." Buzzle Web Portal: Intelligent Life on the Web. 2007. Web. 27 Feb. 2011. .

"NAE Website - Tsunami Warning Systems." National Academy of Engineering. July-Aug. 2005. Web. 27 Feb. 2011. .

"Tsunami Facts, Tsunami Information, Tsunami Videos, Tsunami Photos - National Geographic." Environment Facts, Environment Science, Global Warming, Natural Disasters, Ecosystems, Green Living - National Geographic. National Geographic. Web. 27 Feb. 2011. .

"Tsunami: The Great Waves." NOAA's National Weather Service. National Oceanic and Atmospheric Administration. Web. 27 Feb. 2011. .

Designing a Seismograph

Task: Make a seismograph that detects the Earths movement
Materials: wire, shoebox, washers, string, masking tape, maker, paper.
Original Construction: We made the base of the seismograph out of a box and cut a hole at the top. Through the hole we put the pencil and lots of washer to keep it stable.
Trials with the original construction: the original construction didn't work out because the pencil moved to much and couldn't record.
Modification 1# We added one set of wires to stabilize the pencil.
Trials with Modification 1# The pencil continued to move and the results weren't good we couldn't record anything.
Modification 2# We added a second set of wires lower so it stabilizes the pencil.
Trials with Modification 2# We had a couple trials here and they were all successful the seismograph worked.
Observations:
I noticed that for the seismograph to work we need to make the pencil stationary
I also Noticed that in order for the seismograph to work you need to move the desk in a specific order.
Conclusion: I conclude that Seismographs a really important to scientists. It helps them to measure the magnitude of an earthquake. We can measure when seismic waves start arriving, Scientists can warn people a couple minutes before the earthquakes climax so they get to safety. We can see the magnitude and damage using a seismograph.
Further Inquiry: Does the distance of the seismic waves or the focus affect the readings of the seismograph.

More To Explore: EPICENTER

Depending on the place the city is in the type of earthquake will happen. Each north, south, east, and west have a different type of plate, and depending on the plate the earthquake will happen. (I think so.)

The highest earthquakes are along the Pacific coast. This is in California, Washington and in Alaska. In Washington the earthquakes result from the subduction of the Juan de Fuca plate which is beneath the North American plate. In California, the pacific plate and North American plates meet along the San Andreas Fault. But in Alaska, the subduction of the Pacific plate causes many earthquakes.

The eastern part of the U.S has a lower risk of earthquakes because that region lies far from the plate boundaries. Scientists hypothesize that the continental plate which forms most of the North America is under stress, this stress could probably disturb faults that lie hidden beneath thick layers of soil and rock.

On November 3^rd, 2010, a earthquake happened here in Belgrade with the strength of 5.3, that was the last earthquake we had have in Belgrade for now. Here in Belgrade if we do have earthquakes they are not that hard like in other places. We don’t have earthquakes happening that often, and we hope we don’t start having them.

Earthquakes around the world

Today during class, we were suppose to investigate the earthquakes that were happening around the world. The blue colored line shows where the compression of earthquakes occurred. Compression is when the movement of the tectonic plates causes the rock to squeeze until it folds. As seen in the picture, the compression of earthquakes happened around the Arabian, Eurasian and Philippine plates. The green colored lines shows the tension of the earthquake. Tension is a force that stretches the rock so it becomes thinner somewhere in the middle. The earthquakes that cause tension usually happen around the Indo-Australian and African plates, and a little around the Pacific Ocean (Nazca plate.) The last type of stress that occurred the earthquake is shearing. Which the pink represents. Shearing is when the rocks push in two directions. This can cause the rock to slip apart or change its shape. The earthquakes that cause shearing usually cause a lot of damage and those damages can be really dangerous. The earthquakes shearing happens on the Western part of the U.S and a part of the South American. Shearing also occurred in the Indian Ocean which is really near Australia. The most type of earthquake that occurs I think is tention, this is because, since tension mostly appears in the Indian Ocean, and in the Atlantic Ocean, it affects the lands that are either of the sides of these oceans. I have looked at the data that our teacher Mrs. M gave us, and some of the most devastating earthquakes have happened around South America and the outline of India.

Finding the Epicenter

Guiding Question: How can you locate the earthquake's epicenter?

Hypothesis: We have to find the places where people felt the earthquake, then we have to locate it. Found the distance of the places where people felt the earthquake. and then use a compass to locate the epicenter, and find the place where the lines meet.

Analyze and ConcludeDrawing Conclusion: Observe the three circle you have drawn. Where is the earthquakes epicenter?The epicenter of the earthquake is in Tennessee.Measuring: Which city on the map is closest to the earthquake's epicenter? How far in kilometers, is this city from the epicenter? It was the closest to Nashville. 50 kilometers away from Nashville the epicenter of the earthquake.

Inferring: In which of the three cities listed in the data table would seismographs detect the earthquake first? Last? I think that the first one should be the one that is closest to the epicenter. So, that means the first city that first got detected by the seismograph is Chicago, Illinois. The second one is Houston, Texas, and the last one is Denver, Colorado.

Estimating: About how far from San Francisco is the epicenter that you found? What would be the difference in arrival times of the P and S waves for a recording station in San Francisco? San Francisco is about 3,000 kilometers away from the earthquake's epicenter. The arrival time difference is 5 minutes and 30 seconds.