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A Canadian researcher has discovered that sound travels (21) air more than one-half kilometer an hour slower than had been believed. The discovery has surprised many engineers and scientists who learned they had been (22) the wrong speed of sound for many years.The speed of sound in air had been (23) to be three-hundred-thirty-one-point-two-nine meters a second. But Doctor George Wong found, (24) accident, that the speed of sound is only three-hundred-thirty-one-point-one-three meters a second. That is a difference of about sixteen centimeters a second.Doctor Wong is a member of the National Research Council of Canada. He was studying ways to (25) exactly the sound created by microphones. One of his experiments (26) a number he could use to find the speed of sound. He was (27) to learn that the speed of sound was slower than scientists had thought.To explain the difference, Doctor Wong spent eighteen months (28) past test research on the speed of sound. He finally found the (29) of the difference. It was a mathematics mistake (30) in Nineteen-Forty-Two by physicist H-C Hardy.Doctor Wong’s (31) does not mean a big change for the science of sound. This is (32) Doctor Hardy and Doctor Wong measured the speed of sound for what is called" standard air".Standard air exists only (33) thought. It is a way for scientists to agree (34) the same speed of sound. (35) the air around us, standard air always has a temperature of zero degrees Celsius and the same atmospheric pressure (36) the air at sea level. Standard air always has same amounts of nitrogen, oxygen, carbon dioxide and (37) gases. And in standard air, the speed of sound does not change.The change in the new speed of sound is (38) small to affect the work of most sound scientists and engineers. But scientists say Doctor Wong’s discovery may (39) improve instruments (40) use the speed of sound to measure very short distances. 35().
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A Canadian researcher has discovered that sound travels (21) air more than one-half kilometer an hour slower than had been believed. The discovery has surprised many engineers and scientists who learned they had been (22) the wrong speed of sound for many years.The speed of sound in air had been (23) to be three-hundred-thirty-one-point-two-nine meters a second. But Doctor George Wong found, (24) accident, that the speed of sound is only three-hundred-thirty-one-point-one-three meters a second. That is a difference of about sixteen centimeters a second.Doctor Wong is a member of the National Research Council of Canada. He was studying ways to (25) exactly the sound created by microphones. One of his experiments (26) a number he could use to find the speed of sound. He was (27) to learn that the speed of sound was slower than scientists had thought.To explain the difference, Doctor Wong spent eighteen months (28) past test research on the speed of sound. He finally found the (29) of the difference. It was a mathematics mistake (30) in Nineteen-Forty-Two by physicist H-C Hardy.Doctor Wong’s (31) does not mean a big change for the science of sound. This is (32) Doctor Hardy and Doctor Wong measured the speed of sound for what is called" standard air".Standard air exists only (33) thought. It is a way for scientists to agree (34) the same speed of sound. (35) the air around us, standard air always has a temperature of zero degrees Celsius and the same atmospheric pressure (36) the air at sea level. Standard air always has same amounts of nitrogen, oxygen, carbon dioxide and (37) gases. And in standard air, the speed of sound does not change.The change in the new speed of sound is (38) small to affect the work of most sound scientists and engineers. But scientists say Doctor Wong’s discovery may (39) improve instruments (40) use the speed of sound to measure very short distances. 25().
A Canadian researcher has discovered that sound travels (21) air more than one-half kilometer an hour slower than had been believed. The discovery has surprised many engineers and scientists who learned they had been (22) the wrong speed of sound for many years.The speed of sound in air had been (23) to be three-hundred-thirty-one-point-two-nine meters a second. But Doctor George Wong found, (24) accident, that the speed of sound is only three-hundred-thirty-one-point-one-three meters a second. That is a difference of about sixteen centimeters a second.Doctor Wong is a member of the National Research Council of Canada. He was studying ways to (25) exactly the sound created by microphones. One of his experiments (26) a number he could use to find the speed of sound. He was (27) to learn that the speed of sound was slower than scientists had thought.To explain the difference, Doctor Wong spent eighteen months (28) past test research on the speed of sound. He finally found the (29) of the difference. It was a mathematics mistake (30) in Nineteen-Forty-Two by physicist H-C Hardy.Doctor Wong’s (31) does not mean a big change for the science of sound. This is (32) Doctor Hardy and Doctor Wong measured the speed of sound for what is called" standard air".Standard air exists only (33) thought. It is a way for scientists to agree (34) the same speed of sound. (35) the air around us, standard air always has a temperature of zero degrees Celsius and the same atmospheric pressure (36) the air at sea level. Standard air always has same amounts of nitrogen, oxygen, carbon dioxide and (37) gases. And in standard air, the speed of sound does not change.The change in the new speed of sound is (38) small to affect the work of most sound scientists and engineers. But scientists say Doctor Wong’s discovery may (39) improve instruments (40) use the speed of sound to measure very short distances. 40().
America The Beautiful,is a song almost every American can sing. And while it’s true that The Star Spangled Banner has been America’s official national anthem since 1931 ,many Americans feel a unique affection for the peaceful, patriotic words the poet Katherine Lee Bates was inspired to write during her great journey through the American out West back in 1893. The gently rousing melody, written by the hymnist Samuel Augustus Ward also helped to popularize the song.Willie Nelson’s version of America the Beautiful, is just one of the countless styles in which it’s has been sung. Lynn Sherr, author of America the Beautiful: The stirring True Story of Our Nation’s Favorite Song, seems to appreciate them all. "This is the song that has always given me goose bumps, "she says. "I think it is the quintessentially optimistic vision of America. It is hopeful. It is peaceful. And it just feels great to sing. "Ms. Sherr notes that in each of the song’s four verses, Katherine Lee Bates includes something significant about America to celebrate, something to pray for, and some challenge to overcome. In the beginning of the poem’s familiar first verse, Ms. Bates praised the beauty of the land and its bounty…Thy purple mountains majesties, above the fruited plain, America, America, God shed His grace on thee... Each stanza of Katherine Lee Bates’ famous poem also contains a prayer. Ms. Sherr likes to quote the prayer in the song’s second verse, which says" America, America, God mend thy every flaw ..." "Imagine understanding that America has some flaws and that we are after all a work in progress, "she says. "It is a song of pure patriotism. But it’s not blind patriotism. She knew this was a country that was not perfect. She knew we had a way to go which of course we still do, and yet she still knew that you could know that and still be patriotic. It is important to understand that we are complex human beings and it’s a complex country. We are not perfect but we still love it."Folk singer and left-wing-leaning social activist Pete Seeger whistling the introduction to his version of America the Beautiful. "...And Pete Seeger and understands about patriotism in a way that a lot of Americans didn’t have to, "says Ms. Sherr. "He got into trouble with the law because of some of his [ political ] beliefs. The very fact that he also sings it indicates that, bottom line, he loves America. "Ms. Sherr contrasts the meaning of America the Beautiful with The Star Spangled Banner-a song which also happens to be much harder to sing. "Our actual national anthem, The Star Spangled Banner, was written by a man, Francis Scott Key, who saw a battle and he was writing about a war, "she says. "’ The rocket’s red glare, and the bombs bursting in air...’ This one, on the other hand, is peaceful. It’s about a land and a country, not about a flag and a war."Still, the words to America the Beautiful abound in heroism, as we hear in RayCharles’ iconic rendition of the song, which he began with the third verse. Oh beautiful for heroes proved ,in liberating strife, who more than self their country loved, in mercy more than life..." ’ Oh beautiful for heroes proved,in liberating strife, who more than self their country loved, in mercy more than life...’ I think those words were astounding, and so did he, obviously," says Ms. Sherr. "And I must say they resonate more than ever after 9/11. How can you hear the words’ who more than self their country loved and mercy more than life...’ and not think of all the rescue workers who went into the buildings when everyone else was coming out It’s an amazing thought in that verse and he does it just beautifully...The Ray Charles version is just so exuberant. It’s this kind of bluesy take which of course is pure Ray Charles, very American, very democratic...And this exactly represents Katherine Lee Bates’ point of view... This not an elitist song. This is not for the soldier. This is not for the president only. This is for everybody...’Ms. Sherr says we can think of America the Beautiful not just as an alternative anthem, but, simply, as a song of joy. According to the author, who has introduced his own version of" America the Beautiful" that is not very much popular with American people()
Fireworks are a big part of Fourth of July celebrations in the United States, as hundreds of thousands of Americans enjoyed public pyrotechnic displays across the country Sunday night to celebrate the U.S. birthday. The holiday throws the spotlight on another annual campaign ,an effort to completely ban consumer fireworks in the United States.As Americans around the country watched July Fourth fireworks celebrations, debate has been simmering about whether individuals should be allowed to buy fireworks to celebrate privately. Seven U.S. states prohibit sales of all consumer fireworks. A coalition of groups, led by James Shannon, president of the non-profit fire safety group, the National Fire Protection Association, says that ban should be extended to include the entire United States. "Those fireworks axe inherently dangerous products," he said. "There might be another problem with some of them being designed defectively, so that they are particularly dangerous. But even when they’re designed to do what they’re supposed to do and do it, they can be very, very dangerous products. "Other members of the coalition include the International Fire Chiefs Association and the American Academy of Pediatrics, which has focused on the dangers fireworks pose to children.The U.S. Consumer Product Safety Commission, an independent federal regulatory agency, says fireworks-related accidents in the United States in 2002 killed four people and injured about 8, 800 others in the United States. About haft of the people injured were children, a fact pointed to by Mr. Shannon. "I don’t think serious injury is as American as apple pie, if it’s avoidable. And particularly, if we’re talking about children, thousands and thousands of children, "he said.But fireworks have strong defenders, such as the American Pyrotechnic Association, which says that they are becoming more and more popular in the United States. Officials with the association say that fireworks use in the United States has more than tripled since 1990, to nearly 100-kilograms in 2003. And Ann Crampton, spokeswoman for the National Council on Fireworks Safety, says fireworks are a big part of Fouth of July celebration and their use should not be banned. But Ms. Crampton also says people should exercise care when using them. "We know that millions of people are going to be celebrating with fireworks on the Fourth of July, "she said. "It’s become part of a symbol of this country. Many thousands of people, millions of people, enjoy going to public displays. But there are also people that like to be hands-on and do it themselves in their backyards. We feel they can be safe and they can be injury-free if they choose the right product, know what to choose,what to stay away from."Most of the fireworks sold in the United States come from China. According to the U.S. Census Bureau, Chinese fireworks imports to the United States in 2003 amounted to more than $157-million. Ms. Crampton says the U.S. pyrotechnics industry has been working with Chinese manufacturers to make fireworks safer. "And about 15 years ago, a group was formed, called the American Fireworks Standards Laboratory, to work with Chinese manufacturers, to make sure that the product that they were making meets the safety standards that are required here," she said.The National Fire Protection Association has been lobbying against consumer fireworks sales since 1910. Their efforts are not going to be made any easier by Consumer Product Safety Commission statistics showing that the number of fireworks-related deaths and injuries in the United States has actually fallen in recent years. In defending the firework sale in US, the American Pyrotechnic Association argued().
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