After Friday’s debate and research, my opinion on useing nuclear power is AGAINST. Considering in various aspects, nuclear power has negative impacts in environment, price, unexpected potential energy. First of all, although the amount of emission of greenhouse gase is much lower than other resources like coal, and oil, but nuclear energy can cause environmental problems such as global warming. Also, nuclear power plants can release large quantities of dangerous radioactive materials during accidents, once it happened, it could cause permanent damage to the land and the people. Because the huge influence of nuclear leak, it requires special equipment and container to store and transport nuclear power. Therefore, in order to prevent this type of disease happened, we should use other renewable resources to replace nuclear power weapons, such as wind, solar energy, tidal energy, etc. These are safer and more environment friendly. Though, it has some advantages of using nuclear power, if such terrible things that mentioned above, all the advantages would be wipe out. Another pollution it could produce is water pollutant. While nuclear fission takes place, it needs water to cool it down. Then the water would turn into steam and changes back into liquid form after the process. As a result, theses polluted water escape from chambers and immense to ecosystems nearby the reactor. Secondly, the nuclear fuel is non-renewable resources, as well as building a nuclear energy plant costs rose form between 2 millions and 4 millions per unit to 9 millions per unit. In addition, numerous studies showed the radiation released from plants and industries have high possibilities of leading to cancer. Uranium is one of important materials used in the process of fission. It is an unstable element, which means the workers related to store or transport the materials should take extra precautions, otherwise it will make irreversible damage. Lastly, the one we have to mention is nuclear weapons. We had already seen the impacts can be generated by using weapons in world war. Due to the ambition that some countries have, once the “nuclear war” started, the whole world would end up with incredible devastation. In summary, before scientists coming up the solutions of preventing or reducing the damage the nuclear power would make to people, we should not using nucealr energy in all kinds of areas.
Explanation: In this video, it demonstrates a light trick, about how an object can “Vanish” in the oil. Which used a beaker filled with oil, then simply put in the other smaller beakers, also several stirring rods. At first, when he put the stirring rod into the water, we can clearly see that, but when he put the same stirring rod into the oil, the part of stirring rod in the oil “disappeared”. Then, he showed us, when he put the smaller beaker into the oil, same thing happened, we can barely see the beaker in the water. That’s becuase the index of refraction of oil and stirring rod and other beakers are very similar. Refraction occurs when a wave changes in the direction as it pass from one medium to another. The index of refraction describes how much the light will bend numerically, this number indicated the speed of light in the certain medium. When light passes from air into glass, it slows down. It changed the speed leads to the light reflect and refract. When the difference between the index of refraction of two different materials decreases, the less reflection and refraction while the light travel through two mediums. Therefore, it makes the transparent object looks like “invisible” in that medium.
Description: This video showed one of the wave interferences—Destructive. Which is one end flick the slinky down, and the other end will flick the slinky up at the same time. This experiment demonstrates when one crest met a trough, they will cancel each other out in the middle, and then keep moving to the end with the same amplitude.
Description: In constructive interference, when one crest met another crest (or one trough met another trough), the amplitude of crest would doubled, and then back to the original amplitude and move to the end of string.
Description: non-repeating wave; single disturbance.
Description: wave recurring at regular intervals. Requires regularly repeating disturbances.
Description: spring is pulled sideways (disturbance is at right angle to the direction that the wave will travel)
Description: several turns of the spring are compressed and let go; Disturbance is in the same direction as the direction of travel.
our project is compound pulley system.
Day 1: we simply looked up online of each inventions on the sheet that teacher provided, then we discussed which one is more achievable for us to make, and have the capability to bring or buy the materials
Day 2: we start building up our project with all the materials I brought from home. We decided to use thread rolls as pulleys, and thread as ropes. At jut the first few steps, we got obstacles. How could the thin thread rolling the pulleys if the “pulleys” are too big for it? Through a long time thinking and discussion, we finally figured out what should we do on next day, and what additional materials we need to bring. For example, should we use the third thread roll as load? How should we keep all the pulleys balanced while it’s rolling? Etc.
Day 3: When we realized what was our problem, I came up a solution which is we should use a tall object to be act as pillar, such as a water bottle(though we replaced with bottle of potato chips at last). The purpose of using that is to establish the fixed pulley, so that the whole system has a ending point. Hence we using long ruler(we replaced it with wood board later on) as “celling”, therefore we can stick the rope and fixed pulley on it. Secondly, I got an idea which is use tape to make a little hole on the surface of thread roll (the one act as movable pulley) that could let thread go through it and without lost balance. It did work. Here all problems seems fixed, but the movable pulley did not cooperate very well. When I pulling rope, it did not rolling at all. At first we thought because the edge of thread roll is too rough. Even though we use paper cover all the edge, it is still not work very well, only seldom rolled.
In general, this object was not as easy as I thought before I started. However, I am very glad that my partner kept trying new things, and we have discussions to solve all the difficulties, which is a great help to let this project done perfectly on time.
Archimedes was the first person who point the statement out, make greatly contribution to help people understand the pulley, even though he did not invent any machines of that. Archimedes was the first person documented block and tackle pulley system.
Pulley system was firstly used in water-lifting, people found this method highly improved the efficiency of the force use, and save the amount of force need to apply on the object. This type invention was formally discovered in 1500 b.c. in Mesopotamia area, but at that time they were still using single pulley system. However, about 400 b.c. The Greeks had put to use compound pulleys, or ones that contained several wheels. Plutarch, the Ancient Greek philosopher who developed and invented a pulley machine based on theory of Archimedes. That was known as the Claw of Archimedes, also known as “iron hand”.
Nowadays, compound pulley systems would find application in many things aroun us such as elevators and escalators, also in some theatres still use this system to fly actors.
Description of physics involved in your machine:
Physics involved: In a compound pulley system, it included at least one fixed pulley and one movable pulley. One fixed pulley system would not save force, but it changed the direction of force which convenient the people to contribute force. On the contrary, the movable pulley system can save half force while pulling things up. However, if combined them together, the entire pulley system can saved totally half force. In addition, as you increase the number of the ropes that surround the pulleys, it saved more force. This is a consequence of the tension in any rope is constant, the tension on a rope in a pulley system is the total forcée divided by the number of sections of rope pulling up the mass.
mathematics examples: Due to the compound pulley system uses the work-engery principle. The principle is “work is done by a force(F) pushing over some distance(s). The θ is the angle between the force and the displacement.”
The book “Night” by Elie Wiesel. Generally, this book is taking about the author himself during the WWII, in the concentration camp. All the unforgettable memories during that time period. The story start at when he was still an innocent Jewish teenager, happily lived with his family. However, when the war began, it ruined his life and all the Jewish people’s. They were forced out of their homes, and had to take everything they can bring, then get on the train to the concentration camp unwillingly. That was just the beginning of his nightmare. The condition in the concentration camp is more terrible than he thought. Nazi officers separated the femal and male. Hence, the main character, Elie had to take the responsibility for taking care of himself and his father too. They had a huge amount of work to do everyday, but only get few rotation of bread and soap. Nazi officers treated them inhumanly. They beat Jewish people whenever they want, sometimes just for fun. Some even worse, many Jewish people’s lives ended up with ashes. Also, if the people got sick, or they were considered as too weak to work, that means death. Elie saw many deaths in the concentration camp, he grew stronger mentally. Unfortunately, his father did not survive at the end because of illness.
I like this book, because this is a value of history. Although there are lots of miserable facts happened in this book, however sometimes write these out directly is more powerful. It can easily give readers a sense of how terrible in the concentration camp, and how the wars effects people, especially when a huge group of people suffered just because one person’s ridiculous theory. It is a warning to the people, peace should be the human goal.
Poem by Xuzhimo:
Very quietly I take my leave
As quietly as I came here;
Quietly I wave good-bye
To the rosy clouds in the western sky.
The golden willows by the riverside
Are young brides in the setting sun;
Their reflections on the shimmering waves
Always linger in the depth of my heart.
The floating heart growing the sludge
Sways leisurely under the water;
In the gentle waves of Cambridge
I would be a water plant!
That pool under the shade of elm trees
Holds not water but the rainbow from the sky;
Shattered to pieces among the duck weeds
Is the sediment of a rainbow-like dream?
To seek a dream?
Just to pole a boat upstream
To where the green grass is more verdant
Or to have the boat fully loaded with starlight
And sing aloud in the splendor of starlight.
But I can’t sing aloud
Quietness is my farewell music;
Even summer insects heap silence for me
Silent is Cambridge tonight!
Very quietly I left
As quietly as I came here;
Gently I flick my sleeves
Not even a wisp of cloud will I bring away
Analyze: This is a Chinese poem written by Zhimo Xu , who is one of the most renowned romantic poets of 20th-century Chinese literature, he is known for his promotion of modern Chinese poetry and made contributions to modern Chinese literature. He was born in a very rich family, his father has family business, at that time period, his family was the top rich people in that town, so Zhimo Xu can go to school when he was a little, and always can get the best education, that made his family hope he could become the best student, and also created the firm foundation which helped him can go to notable foreign universities. He attended Clark University in America in 1918, after 10 months, he transferred to Columbia University in the City of New York, to learn economy. Furthermore, in 1921 he attended Cambridge university in Britain to study Political Economy. The two years in Cambridge was a very important time period of Zhimo Xu, because he was impacted by the Western poets, which made he start writing poems, and become Romanticism. Even in 1923, he set up Xinyue(new moon) Club in Beijing. Unfortunately, he died in a airplane crash in November, 1931. Though this is poem was written in Chinese, and translated into the English version. I chose this poem, because it is very famous poem in China, the original version has many beautiful and meaningful words, which creates the mood and the theme of the poem. It seems like it is describing the scenery of Cambridge, but the author expressed his emotions rely on these natural objects indeed. The emotions have three parts: missing the place which “bring up” him, because the Cambridge brought him onto the poet path; pity to leave this wonderful place, and he recalled sweet memories with a girl he met in Cambridge. Under the charming scenery, the love relationship made him very gloomy. The speaker is the author, and the audience is the Cambridge university. The tone of the poem is sad, shows the narrator is reluctant to leave this place. Therefore the music that my group chose which also gives people a sorrowful, but quiet and peaceful feelings, that is one of the reasons we chose; another one would be this poem was written on November 6th, 1928, so the song’s atmosphere fits in that time period. I did not give a background to the title in the video, because I think that would be clear to the audiences. For the first two lines of the poem are talking about the narrator came to and then left Cambridge without anyone knowing, very brief and clear, so I chose the picture of the Cambridge university under the blue sky and white clouds, which could show narrator carried a cheerful mood came here secretly. Because this was written on the way back home, so the start of the poem takes about leaving. Straight afterward, the author begin depicting the scenery he saw, so my group chose the pictures just fit in the poem directly for the next 6 lines; And then we chose a picture of a flying dandelion in the sunset. Firstly, these two lines seems are talking about the plants grow in the water, apparently the author uses this little grass to express his longing for freedom, that just suitable for the flying dandelion; secondly, the narrator went there when the sunset, that is the reason the picture has the sunset. Subsequently, the next picture shows the mom hug her child in her bosom, because in the poem, the “gentle waves” and water plant is living in the water, it relies on the water to live, as a result these two lines reveal the narrator felt the connection between him and the Cambridge just like this place is his mother gave him a new life. In the next two lines, the picture just simply about the river under the little arch bridge, the sunset, the sky reflects on the water surface. But I think the author wants to say more than that, connect to the line before, the pool is the one that water plant grows. Although, the water plant in the water, the pool also has the rainbow from the sky, which stands for the dream that the author had, or probably stands for the sweet memories when he was still a student. Then, next two lines make the rainbow more clearly, which are saying the pool shattered the rainbow into pieces, and they become the sediment, so the water plant can have the “rainbow-like dream”which is a metaphor. In the picture the girl is blowing a big bubble, and the goldfish flowing in the air, it shows the dream, and amazing alike the rainbow. The 17th line is very short, the funny thing is in the Chinese version, it is only 2 words, it is about seeking dream, so we think the girl running by the riverside or ocean line is full of youthful spirit, illustrate the power that people who is putting efforts to reach their goals properly. The next two lines, the author wants to say if you want to seek the dream, you need to go to where the green grass is more verdant, only the grass is delicate could be more verdant, likewise the upstream has the same meaning likewise. It is a metaphor, author is telling readers the time when he was a student, he had the dreams. So we chose the picture whixh is actually a photo of the author when he was younger. Then another metaphor appears in the next two lines. “The boat fully loaded with starlight” demonstrate the dreams, as shinning as the starlight, as beautiful as starlight. I chose the picture that a boat berths in the middle of the ocean, and the sky in the night has lots of beautiful starlight. This is picture seems very straight forward, but I think it also give people a feeling that the boat is losing in the beautiful starlight, intoxicated in the pleasant scenery, just like the narrator really missed that time which full of dreams and enthusiasm. We chose a picture of seedling, because we think it is showing vigor, just like the poem “sing aloud”, has the vitality. Instead, the dream did not came true, as the next two lines tell us, the narrator seems like trapped, had the limitation to sing aloud, only “quietness””even summer insects heap silence for me”. Because the author went back to the Cambridge by himself without anyone knowing, and he did not meet his old friends, so he wanted to shout out his feelings, his thoughts, but they were nowhere to go. So we chose a picture which a girl draw a sad face on the paper, fully fit for the mood the narrator had, and then next picture is a man walking on the bleak street, only himself and it is raining, just like the tone that narrator portrayed..As a result, in the next line, narrator keeps talking about the silent, but very simple, so I chose the picture that Cambridge in the sunset, and no one is there. Lastly, there is a repetition of the first verse, so the same picture as the beginning, but the Cambridge is in the night. Then instead of wave goodbye, author changed words, “flick my sleeves” and “..wisp of cloud” it shows the emotion that narrator was reluctant to leaving, but also reveals the narrator felt free after revisiting, I can also feel the narrator has no alternative, he has nothing to bring back, that is a pity to narrator. The title of the poem is “Saying Goodbye to the Cambridge again”, because after his graduation, this is the second goodbye. Basically, the poem talks about the narrator came back to the Cambridge, who enjoyed the scenery at first, then recalled lots of memories in school time, after that left with a bunch of sadness. The original version, every four lines is a stanza, the last word in the end of the second line matches the forth line’s, as well as the first matches the third one, this is rhyme, but in the English version, it does not have, so it could also be free verse.The shift in the poem would be the third verse, which is the 9th line. From the 9th line it starts talking about the dreams, the poem becomes abstract from concrete, then at last six lines become concrete again. The whole poem is from general to specific, at the beginning tells everyone the narrator left the Cambridge, then reminisce the time in university, talking in specific, especially the stanza talks about the dream. In general, we could see the poem is from question to answer. Initially, the author came back want to find his girlfriend, but she left before, moreover, he did not meet any friends there, the loneliness. Dramatically, because of the attractive views beneath sunset made the author set a goal, recall the eagerness to seek a dream, so it could be considered as the author found his answer. Many connotation in the poem, such as the vocabulary “floating heart” which is not just a type of plant, but it is narrator himself; “sing aloud” is not real singing, it is a way that stands for narrator want to yell out his feelings. Other poetic devices would be: “summer insects heap silence for me” is a personification; “The golden willows by the riverside, Are young brides in the setting sun””Always linger in the depth of my heart” are metaphor. The description of water plant and starlight could also be imagery. “Or to have the boat fully loaded with starlight” is hyperbole. To me, I feel connection with this poem, I am living in the foreign country now, receiving education here and also I will go to a university here in the future, I also long for the happy days I can have in the university, and also craves to fall in love with a handsome boy.