Latent Heat of Vaporization of Water Essays

Latent Heat of Vaporization of Water Essays Latent Heat of Vaporization of Water Paper Latent Heat of Vaporization of Water Paper Uncertainty in measuring time was  ±0. 01s according to the stopwatch but while measuring mass you have to first look at the time in stopwatch and then the mass in the electronic balance and because humans cannot react instantly it is estimated to be  ±1s. Uncertainty in measuring mass of the water was  ±0. 1g because it was measured using a weighing machine with the  ±0. 1g uncertainty. The graph of mass of water evaporated over time is linear because the best fit line passes through all error bars. From the calculations the specific latent heat of vaporization of water is calculated to be 2500 J/g  ±60 J/g. The literature value of specific latent heat of vaporization of water is 2260 J/g, which is quite low. The total percent error is 10. 6% and the total percent uncertainty is 2. 5% which is quite low compared to the percentage error. 2. 5% uncertainty means the final result can be  ±2. 5% off. That means the total error caused by uncertainties is 2.5%, rest is from systematic errors. One of the biggest systematic errors could be the heat loss from the water to the atmosphere. A well-insulated plastic kettle was used to boil the water so there will be minimum heat loss from water to kettle and kettle to surroundings. If the heat is lost to the surroundings from water, it means that the power supplied by the kettle is not completely used to boil water as it is lost in the surrounding so the power supplied is less than 1000W. While recording the mass of water, the mass of the water in the electronic balance was not constantly decreasing. Sometimes it increased, sometimes it decreased slowly and sometimes rapidly and because of this there was a high error in collecting data. An electronic balance with high mass capturing should have been used for better results. The electronic balance used did not have a wide base and the kettle used to boil water was overturning it which also can result in high error. An electronic balance with wide base should be used for more accurate results.

SB2C Helldiver - Curtiss SB2C Helldiver

SB2C Helldiver - Curtiss SB2C Helldiver SB2C Helldiver - Specifications: General Length: 36 ft. 9 in. Wingspan: 49 ft. 9 in. Height: 14 ft. 9 in. Wing Area: 422 sq. ft. Empty Weight: 10,114 lbs. Loaded Weight: 13,674 lbs. Crew: 2 Number Built: 7,140 Performance Power Plant: 1 Ãâ€" Wright R-2600 radial engine, 1,900 hp Range: 1,200 miles Max Speed: 294 mph Ceiling: 25,000 ft Armament Guns: 2 Ãâ€" 20 mm (.79 in) cannon in the wings, 2 Ãâ€" 0.30 in M1919 Browning machine guns in rear cockpit Bombs/Torpedo: Internal bay - 2,000 lbs. of bombs or 1 Mark 13 torpedo, Underwing Hard Points - 2 x 500 lb. bombs SB2C Helldiver - Design Development: In 1938, the US Navys Bureau of Aeronautics (BuAer) circulated a request for proposals for a for a next-generation dive bomber to replace the new SBD Dauntless. Though the SBD had yet to enter service, BuAer sought an aircraft with greater speed, range, and payload. In addition, it was to be powered by the new Wright R-2600 Cyclone engine, possess an internal bomb bay, and be of a size that two of the aircraft could fit on a carriers elevator. While six companies submitted entries, BuAer selected Curtiss design as the winner in May 1939. Designated the SB2C Helldiver, the design immediately began showing problems. Early wind tunnel testing in February 1940 found the SB2C to have an excessive stall speed and poor longitudinal stability. While efforts to fix the stall speed included increasing the size of the wings, the latter issue presented greater problems and was a result of BuAers request that two aircraft be able to fit on an elevator. This limited the length of the aircraft despite the fact it was to have more power and a greater internal volume than its predecessor. The result of these increases, without an increase in length, was instability. As the aircraft could not be lengthened, the only solution was to enlarge its vertical tail, which was done twice during development. One prototype was constructed and first flew on December 18, 1940. Built in a conventional fashion, the aircraft possessed a semi-monocoque fuselage and two-spar, four-section wings. The initial armament consisted of two .50 cal. machine guns mounted in the cowling as well as one in each wing. This was supplemented by twin .30 cal. machine guns on a flexible mounting for the radio operator. The internal bomb bay could carry a single 1,000 lb. bomb, two 500 lb. bombs, or a torpedo. SB2C Helldiver - Problems Persist: Following the initial flight, problems remained with the design as bugs were found in the Cyclone engines and the SB2C showed instability at high speed. After a crash in February, flight testing continued through the fall until December 21 when the right wing and stabilizer gave out during a dive test. The crash effectively grounded the type for six months as the problems were addressed and the first production aircraft built. When the first SB2C-1 flew on June 30, 1942, it incorporated a variety of changes which increased its weight by nearly 3,000 lbs. and reduced its speed by 40 mph. SB2C Helldiver - Production Nightmares: Though unhappy with this drop in performance, BuAer was too committed to the program to pull out and was forced to push ahead. This was partly due to an earlier insistence that the aircraft be mass-produced to anticipate wartime needs. As a result, Curtiss had received orders for 4,000 aircraft before the first production type flew. With the first production aircraft emerging from their Columbus, OH plant, Curtiss found a series of problems with the SB2C. These generated so many fixes that a second assembly line was built to immediately modify newly built aircraft to the latest standard. Moving through three modification schemes, Curtiss was not able to incorporate all of the changes into the main assembly line until 600 SB2Cs were built. In addition to the fixes, other alterations to the SB2C series included the removal of the .50 machine guns in the wings (the cowl guns had been removed earlier) and replacing them with 20mm cannon. Production of the -1 series ended in spring 1944 with the switch to the -3. The Helldiver was built in variants through -5 with key changes being the use of a more powerful engine, four-bladed propeller, and the addition of wing racks for eight 5 in. rockets. SB2C Helldiver - Operational History: The reputation of the SB2C was well known before the type began arriving in late 1943. As a result, many front-line units actively resisted giving up their SBDs for the new aircraft. Due to its reputation and appearance, the Helldiver quickly earned the nicknames Son of a Bitch 2nd Class, Big-Tailed Beast, and just Beast. Among the issues put forward by crews in regard to the SB2C-1 was that it was underpowered, poorly built, possessed a faulty electrical system, and required extensive maintenance. First deployed with VB-17 aboard USS Bunker Hill, the type entered combat on November 11, 1943 during raids on Rabaul. It was not until spring 1944 that the Helldiver began to arrive in larger numbers. Seeing combat during the Battle of the Philippine Sea, the type had a mixed showing as many were forced to ditch during the long return flight after dark. Despite this loss of aircraft, it sped the arrival of improved SB2C-3s. Becoming the US Navys principal dive bomber, the SB2C saw action during the remainder of the conflicts battles in the Pacific including Leyte Gulf, Iwo Jima, and Okinawa. Helldivers also took part in attacks on the Japanese mainland. As later variants of the aircraft improved, many pilots came to have a grudging respect for the SB2C citing its ability to sustain heavy damage and remain aloft, its large payload, and longer range. Despite its early problems, the SB2C proved an effective combat aircraft and may have been the best dive bomber flown by the US Navy. The type was also the last designed for the US Navy as actions late in the war increasingly showed that fighters equipped with bombs and rockets were as effective as dedicated dive bombers and did not require air superiority. In the years after World War II, the Helldiver was retained as the US Navys prime attack aircraft and inherited the torpedo bombing role previously filled by the Grumman TBF Avenger. The type continued to fly until it was finally replaced by the Douglas A-1 Skyraider in 1949. SB2C Helldiver - Other Users: Watching the success of the German Junkers Ju 87 Stuka during the early days of World War II, the US Army Air Corps began looking for a dive bomber. Rather than seek a new design, the USAAC turned to existing types then in use with the US Navy. Ordering a quantity of SBDs under the designation A-24 Banshee, they also made plans to purchase a large number of modified SB2C-1s under the name A-25 Shrike. Between late 1942 and early 1944 900 Shrikes were built. Having re-assessed their needs based on combat in Europe, the US Army Air Forces found these aircraft were not needed and turned many back to the US Marine Corps while some were retained for secondary roles. The Helldiver was also flown by the Royal Navy, France, Italy, Greece, Portugal, Australia, and Thailand. French and Thai SB2Cs saw action against the Viet Minh during the First Indochina War while Greek Helldivers were used to attack Communist insurgents in the late 1940s. The last nation to use the aircraft was Italy which retired their Helldivers in 1959. Selected Sources Ace Pilot: SB2C HelldiverMilitary Factory: SB2C Helldiver Warbird Alley: SB2C Helldiver