H.S. Level - SOund And Light Waves :: essays research papers

Sounds are produced by the vibrations of material objects, and travel as a result of momentum transfer when air molecules collide. Our ‘subjective impression’ about the frequency of a sound is called pitch. High pitch has high vibration frequency, while low pitch has a low vibration frequency. A pure musical tone consists of a single pitch or frequency. However, most musical tones are â€Å"complex summations† of various pure frequencies - one characteristic frequency, called the fundamental, and a series of overtones or harmonics Younger people can usually hear pitches with frequencies from about 20 hertz (infrasonic) to 20,000 (ultrasonic) hertz. We can’t hear above 20,000 hertz or below 20 hertz (ultra and infrasonic waves). Light is both part particle and part wave. Light is â€Å"the electromagnetic radiation that may be perceived by the human eye†. It consists of photons, which are massless bundles of concentrated electromagnetic energy. Light’s lower frequency is red, and the higher frequency is blue. Like sound, light has frequencies humans can’t detect. Ultraviolet light is at a frequency higher than violet, and infrared is at the frequency lower than the red of visible light. We get UV (ultraviolet) rays from the sun, and infrared is used in night vision to see better. Sound travels at about 1,200 k/hr while light travels at about 300,000 km/s. It’s easy to notice how slowly sound travels. Take, for instance, a soccer field. If you were standing at one end and you see somebody kick the ball, it will probably take a second for you to hear the person kick it. You hear the sound a few seconds after you see the ball moving. The farther you are away, the longer the space is between you seeing the ball being kicked and you actually hearing it. Light can travel around the earth 7 and a half times in one second. Light and sound are similar in some ways too, though. They both have frequencies that humans cannot detect (ultraviolet, infrasonic, etc.). Since both of them are also waves, they can be made to interfere. They can also be made to reflect and refract. As said above, both light and sound waves have to do with interference. In sound, interference affects both the loudness and amplitude. When two waves’ crests overlap, the amplitude increases. The same is true with the troughs of the waves, which decrease the amplitude.

Career Interest Profiler

The results from my interest profiler were enterprising occupations, social occupations and conventional occupations. Enterprising occupations include starting up and carrying out projects. These occupations can involve leading people and making many decisions. Sometimes they require risk taking and often deal with business. Social occupations frequently involve working with, communicating with, and teaching people. These occupations often involve helping or providing service to thers and conventional occupations frequently involve following set procedures and routines.These occupations can include working with data and details more than with ideas. Usually there is a clear line of authority to follow. The results of my competencies were organizing, strategizing, innovating, following instructions, adapting to change and entrepreneurial thinking. As stated in my career plan a lawyer, Judge, supervisor of an office, administrative support worker, upervisor of protective service worker s and supervisor of sales workers were examples of possible Job titles that matched my competencies.According to my career plan the first result of my work culture preferences was supportive which includes a secure, stable environment, clearly defined Jobs, goals and expectations, no conflicting demands, considerate management, focuses on employee welfare, lots of personal development and feedback, lots of recognition and celebration of success and a fun place to work.The second result was high powered which includes demanding Jobs, career development, career advancement, the chance to learn new skills, the chance to try different Jobs or work in different places, high salaries, likelihood of rapid promotion and other benefits. Last, but not least the third result was ethical which includes emphasis on fairness, active promotion of equal rights and Justice for all, the chance to contribute positively to society and make a difference to people's lives and an emphasis on social and en vironmental esponsibility.After taking the assessments for my career interest profiler, competencies and work culture preferences, I have gained a lot of useful information about myself as well as in regards to what specific characteristics I possess and what type of employment opportunities I should be searching for. There was a ton of information to consider after looking at the results, but I feel as though I can take this information and apply it to my life as I am looking to advance within my career.

Supermarine Spitfire in World War II

The iconic fighter of the Royal Air Force in World War II, the British Supermarine Spitfire saw action in all theaters of the war. First introduced in 1938, it was continually refined and improved through the course of the conflict with over 20,000 built. Best known for its elliptical wing design and role during the Battle of Britain, the Spitfire was beloved by its pilots and became a symbol of the RAF. Also used by British Commonwealth nations, the Spitfire remained in service with some countries into the early 1960s. Design The brainchild of Supermarines chief designer, Reginald J. Mitchell, the Spitfires design evolved during the 1930s. Utilizing his background in creating high-speed racing aircraft, Mitchell worked to combine a sleek, aerodynamic airframe with the new Rolls-Royce PV-12 Merlin engine. In order to meet the Air Ministrys requirement that the new aircraft carry eight .303 cal. machine guns, Mitchell chose to incorporate a large, elliptical wing form into the design. Mitchell lived just long enough to see the prototype fly before dying of cancer in 1937. Further development of the aircraft was led by Joe Smith. Production Following trials in 1936, the Air Ministry placed an initial order for 310 aircraft. To meet the governments needs, Supermarine built a new plant at Castle Bromwich, near Birmingham, to produce the aircraft. With war on the horizon, the new factory was built quickly and it began production two months after the ground breaking. Assembly time for the Spitfire tended to be high relative to other fighters of the day due to the stressed-skin construction and the complexity of building the elliptical wing. From the time assembly began to the end of World War II, over 20,300 Spitfires were constructed. Evolution Through the course of the war, the Spitfire was repeatedly upgraded and altered to ensure that it remained an effective frontline fighter. Supermarine produced a total of 24 marks (versions) of the aircraft, with major changes including the introduction of the Griffon engine and varying wing designs. While originally carrying eight .303 cal. machine guns, it was found that a mixture of .303 cal. guns and 20mm cannon was more effective. To accommodate this, Supermarine designed the B and C wings which could carry 4 .303 guns and 2 20mm cannon. The most produced variant was the Mk. V which had 6,479 built. Specifications - Supermarine Spitfire Mk. Vb General Crew: 1Length: 29 ft. 11 in.Wingspan: 36 ft. 10 in.Height: 11 ft. 5 in.Wing Area: 242.1 sq. ft.Empty Weight: 5,090 lbs.Max Takeoff Weight: 6,770 lbs.Power Plant: 1 x Rolls-Royce Merlin 45 Supercharged V12 engine, 1,470 hp at 9,250 ft. Performance Maximum Speed: 330 knots (378 mph)Combat Radius: 470 milesService Ceiling: 35,000 ft.Rate of Climb: 2,665 ft/min. Armament 2 x 20mm Hispano Mk. II cannon4 .303 cal. Browning machine guns2x 240 lb. bombs Early Service The Spitfire entered service with 19 Squadron on August 4, 1938. Successive squadrons were equipped with the aircraft over the following year. With the beginning of World War II on September 1, 1939, the aircraft commenced combat operations. Five days later, Spitfires were involved in a friendly fire incident, dubbed the Battle of Barking Creek, which resulted in the first RAF pilot death of the war. The type first engaged the Germans on October 16 when nine Junkers Ju 88s attempted to attack the cruisers HMS Southampton and HMS Edinburgh in the Firth of Forth. In 1940, Spitfires took part in the fighting in the Netherlands and France. During the latter battle, they aided in covering beaches during the evacuation of Dunkirk.   Battle of Britain Spitfire Mk. I and Mk. II variants aided in turning back the Germans during the Battle of Britain in the summer and fall of 1940. While less numerous than the Hawker Hurricane, Spitfires matched up better against the principal German fighter, the Messerschmitt Bf 109. As a result, Spitfire-equipped squadrons were frequently assigned to defeating the German fighters, while the Hurricanes attacked the bombers. In early 1941, the Mk. V was introduced, providing pilots with a more formidable aircraft. The advantages of the Mk. V were quickly erased later that year with the arrival of the Focke-Wulf Fw 190. Service Home Abroad Beginning in 1942, Spitfires were sent to RAF and Commonwealth squadrons operating abroad. Flying in the Mediterranean, Burma-India, and in the Pacific, the Spitfire continued to make its mark. At home, squadrons provided fighter escort for American bombing attacks on Germany. Due to their short range, they were only able to provide cover into northwest France and the Channel. As a result, escort duties were turned over to American P-47 Thunderbolts, P-38 Lightnings, and P-51 Mustangs as they became available. With the invasion of France in June 1944, Spitfire squadrons were moved across the Channel to aid in obtaining air superiority. Late War After Flying from fields close to the lines, RAF Spitfires worked in conjunction with other Allied air forces to sweep the German Luftwaffe from the sky. As fewer German aircraft were seen, they also provided ground support and sought out targets of opportunity in the German rear. In the years following the war, Spitfires continued to see action during the Greek Civil War and the 1948 Arab-Israeli War. In the latter conflict, the aircraft was flown by both the Israelis and Egyptians. A popular fighter, some nations continued to fly the Spitfire into the 1960s. Supermarine Seafire Adapted for naval use under the name Seafire, the aircraft saw the majority of its service in the Pacific and Far East. Ill-suited for deck operations, the aircrafts performance also suffered due to the additional equipment required for landing at sea. After improvement, the Mk. II and Mk. III proved superior to the Japanese A6M Zero. Though not as durable or as powerful as the American F6F Hellcat and F4U Corsair, the Seafire acquitted itself well against the enemy, particularly in defeating kamikaze attacks late in the war.