Genesis Of Army Air Defence History Essay

Genesis Of Army Air Defence History Essay What happened in Kuwait Iraq necessitates a review of the attitude towards the army air defence and the countrys entire AD systemà ¢Ã¢â€š ¬Ã‚ ¦.. When we ask ourselves, did it work in Iraq, we have the answer, mostly it did not. Russian Minister of Defence Yazov NATO defines air defence as all measures designed to nullify or reduce the effectiveness of hostile air action. They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces wherever they are. However, for most countries the main effort has tended to be homeland defence. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare  [2]  . Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting potentially any projectile in flight. In some countries, such as Britain and Germany in World War II, the Soviet Union and NATOs European Command, ground based air defence and air defence aircraft have been under integrated command and control. Nevertheless, while overall air defence may be for homeland defence including military facilities, forces in the field, wherever they ar e, invariably deploy their own air defence capability generally referred to as Army Air Defence. A surface based air defence capability can also be deployed offensively to deny the use of airspace to an opponent. This is the central idea of this article. THE EVOLUTION There are two things that make Air Defence (AD) necessary something to defend and an airborne threat. The threat from air existed earlier than the airplane. There existed a concept of air defence much before the Write Brothers flew the first aircraft in 1903. In August 1861, an American Aeronaut while on his balloon, reported the first anti aircraft fire  [3]  . This was one of the pioneering attempts in active air defence. The air defence artillery (ADA) began its evolution, when Col RP Davidson of USA built the first automatic AD weapon around 1909  [4]  . However, very little work was done in the field of AD Doctrine, as the military leaders were yet to realize the importance of air defence. The substantial air threat encountered in World War I triggered the development of dedicated ADA. In 1914, when the Allied air attacks on Germany became more persistent, the Germans exploited this new weaponry and called it Flugzug Abwehr Kanomen or Flak  [5]  . Sound location and search lights were the main means of surveillance. The establishment of London Air Defence Area (LADA) in July 1917, was pivotal as it was the first step towards centralization integration of assets like FF units, AA Gun Batteries Search Light Batteries into one entity. At the end of World War I, to facilitate quick demobilization, the AD elements of great powers were broken up. During the inter-war period with the evolution of AF, to control Englands airspace Air Defence Great Britain (ADGB) was formed in 1925. This was the first time AF was integrated for the AD which had two distinct elements: Royal AF Bombing Formations and the Fighting Area. Fighting Area was made up of ten sectors under GOC Ground Troops who would control all ground base elements of AD  [6]  . The Garrison Artillery was also abolished and its AD units were transferred to Field Artillery. In 1930s the development of radars brought about another renaissance for the AD and fostered induction of surveillance radars and better guns. The Abyssinian Crisis in October 1935 saw the first overseas deployment of AD, when the 1st AD Brigade was deployed in Egypt to protect the English against Italian attacks. The Ground Commander continued to be in charge of the local air defences as he could coordinate allocation of resources, Passive AD (PAD) measures and deception. Procedural Air Control measures were conceived by the Japanese after the US Doolittle Raids on Japan in 1942  [7]  . However, at no time were the interceptors and ADA placed under a single commander  [8]  . The Japanese defeat through air power is one classic example of the enormous price a nation had for inadequacies and poor air defences. It was Japanese air threat in SE Asia during the Second World War which forced British Government to raise AD units in India. Thus the history of AD Artillery in India began 1939 onwards when a few Indian troops began to be trained in the use of the 3 inch gun as part of the Anti-aircraft (AA) Batteries of Hongkong and Singapore Royal Artillery (HKSRA) and Indian Artillery. From 1941 onwards AA units and training establishments began to be raised in India.  [9]  The orgaisation of AA units and formations, though akin to artillery for command and control, evolved on the basis of gun density requirement for protection of Vulnerable Points and Areas. During the World War II, the Indian LAA Regiments were awarded for their dedication and acts of valour in the face of the enemy. At the time of partition only two AD Artillery units viz 26 LAA and 27 LAA Regiments came to India while the oldest AA Establishment the 1 Training Battery failed to survive the partition  [10]  . We have come a long way since then, graduating from ACK ACK (AA) to the Air Defence Branch of Regiment of Artillery, creation of a separate Corps of AD Artillery in 1994 and then renaming it as Corps of Army Air Defence in 2005  [11]  . However, a lot of ground still remains uncovered and today in spite of having AIR DEFENCE ARTILLERY OF USA Air Defence Artillery originated from the Coast Artillery Corps which was created after the Revolutionary War to defend the US coasts against naval attack and bombardment. As the US entered World War I in 1917, Coast Artillery units were detailed as Anti Aircraft Artillery(AAA) units. Weapons for these units were procured from France (75 mm Guns) but there was no doctrine. These units entered World War II beginning with the engagement of the Japanese at Pearl Harbor. German V2 Rockets led to the development of US field missile systems. Today AAA refers to the combat group that specializes in anti-aircraft weapons (such as surface to air missiles). In the US Army, these groups are composed of mainly air defence systems such as the PATRIOT Missile System, Terminal High Altitude Air Defence(THAAD), and the Avenger Air Defense system which fires the FIM-92 Stinger missiles. The Air Defence Artillery branch descended from the Anti-Aircraft Artillery (part of the Field Artillery) into a se parate branch on 20 June 1968  [12]  . Eqpt. Corps AD/EAC DIVAD FUTURE DEVP REMARKS PAC 2 GEM (100KM/ 55KM)* AVENGER SLAMRAAM *RANGE/ ALTITUDE PAC 3 (100/ 55) STINGER MEADS THAAD (200/ 150) BSFV C-RAM LINEBACKER SLAMRAAM :Surface Launched Advance Medium Range Air to Air Missile MEADS: Medium Extended AD System BSFV: Bradley Stinger Fighting Vehicle C-RAM: Counter Rocket, Arty Mortar Division Air Defence(DIVAD) Units. These are Short Range Air Defence (SHORAD) battalions tailor made for the formations they support with each of them having about three to four batteries. Infantry, Mechanised Infantry, Armoured, Air Assault and Air Borne Divisions have their own DIVAD battalions. Non DIVAD units. These are High and Medium Air Defence(HIMAD) Battalions at both Corps and Echelons Above Corps (EAC) levels equipped with Patriot THAAD systems. The Patriot Battalions have about five batteries. Patriot is a long-range, high and medium altitude, all-weather Air Defence system to counter Tactical Ballistic Missiles(TBMs), cruise missiles and advanced air craft. The current force of 12 Patriot Bns, 13 Avenger Bns four AMD Bns is planned to be reorganized into 16 AMD Bns ( equipped with MEADS/ THAAD) nine SLAMRAAM Bns. The 32d Army Air and Missile Defense Command (AAMDC) is a one-of-a-kind theater level Army air and missile defense multi-component organization with a worldwide, 72-hour deployment mission. 32d AAMDC consists of two brigades, 11th Air Defense Artillery and 35th Air Defense Artillery; both stand ready to accomplish any mission anywhere, anytime in support of the warfighting CINC. Recent contingency deployments to Southwest Asia and an intense exercise schedule in Korea exemplify the vital role and mission that the organization plays  [13]  . The Army Air and Missile Defence Command (AAMDC) is the Armys combat organization for planning, coordinating, integrating, and executing AD operations in support of the army service component commander (ASCC), the Army forces (ARFOR) commander, the joint force land component commander (JFLCC).  [14]  A majority of air and missile defence (AMD) coordination of interest to ADA occurs between the Area Air Defence Commander (AADC) and the JFLCC in most theatres. The JFLCC integrates Army capabilities into joint air and missile defence efforts through close coordination with the AADC. When the AAMDC is in theatre, the AAMDC commander will normally be designated the DAADC and will be the principal integrator for the JFLCC to the AADC on air and missile defence. An AAMDC liaison team works closely with the AADC and his staff and the BCD (Battle Space Coordination Center) to accomplish air and missile defence integration  [15]  . THE AIR DEFENCE OF RUSSIA The first Soviet AD Units was raised with the est of 1st AAA Regt at Leningrad in 1924. The air def directorate was formed in 1932. In November 1941, motivated by increasing German raids on Moscow Leningrad, National Air Defence Forces or PVO Strany was formed and in 1948 it became a separate service  [16]  . The organisation of PVO was very peculiar as it had its separate AD air crafts. The Air Defence Forces formerly the Air Defense Troops of the Nation (Russian: à Ã¢â‚¬â„¢Ãƒ Ã‚ ¾Ãƒ Ã‚ ¹Ãƒâ€˜Ã‚ Ãƒ Ã‚ ºÃƒ Ã‚ ° à Ã… ¸Ãƒ Ã¢â‚¬â„¢Ãƒ Ã… ¾, Voyska ProtivoVozdushnoy Oborony, Voyska PVO and formerly ProvitoVozdushnaya Oborona Strany, PVO Strany) was the air defence branch of the Soviet Armed Forces  [17]  . By 1958 separate service , AD of ground troops PVO SV was established which was responsible for AD of army assets. Operating two different ADs, PVO Strany PVO SV and also two different AFs had its inherent command control problems. So, in 1981 PVO Strany was reorga nised and its name was changed to Voyska PVO (AD Tps). The Army Air Def was made subordinate branch to Voyska PVO and was called the AD of Troops (Voyskovaya PVO). Prior to dissolution of Soviet Union, PVO was the second largest independent service of Soviet armed Forces and it consumed major share of military allocation.  [18]  On disintegration of the Soviet Union, President Yeltsin signed a new defence policy document in Aug 1998 which established a single system of military administrative division of Russian territory. This replaced the earlier military districts with six integrated strategic areas or Zones. In 1998 the AD was merged with the Air Force (VVS) and by 2003 the RVSN i.e Strategic Missile Force Army Aviation units were merged with AF. The AF is organised into six Air AD armies which are operationally under op control of military zone/district commanders. Each zone is divided into AD Districts Districts are further divided into AD Sectors . Air defence of impor tant areas is under Missile Bdes. Air surveillance and intelligence is responsibility of Radio Brigades. The overall AD system of Russian includes :- Space defence troops. AD troops (Strategic). Army AD Troops. Naval Anti Aircraft Troops. D:Documents and SettingsAdm TrgDesktopCapture456.PNG Eqpt. MISSILE BRIGADES ARMY AD TROOPS FUTURE DEVP REMARKS SA-3 PECHORA (25KM/ 15KM)* SA-6 KVADRAT/ SA- 11 GRADFLY SA-20 TRIUMF S-400(400/30) *RANGE/ ALTITUDE SA-10 GRUMBLE (200/ 90) SA -8 OSA AK/ SA-15 PANTZYR S1 SPAD (4/6) SA-12 GLADIATOR (90/ 15) SA-19 TUNGUSKA DZHIGIT(SA 16/18) SA-17 BUK M2 (42/25) $ SA-18 IGLA 2/S ANTEY 2500/ S-300 VM (200/30) $ 4 TH GENERATION SA-5 GAMMON (200/20) KS 30/ S-60/ ZU 23 @ @ GUN SYS Russian AD doctrine is defensive in nature. The anti aircraft fire is coordinated by the AD Sector and AD Missile Brigades are responsible for fire control in a specific sector. The overall AD network is completely integrated with Ranzir CP, Baikal IE systems and Polyana 4E systems  [19]  , for each level, which get inputs from AWACS through compatible integrated data transfer system. They have developed the S- 300 series S-400 series of Missiles which are Counter Missile system. The deployment of S-400 began in 2007 and is likely to be completed by 2015.  [20]  The Russian R D is now focusing on point AD systems Counter missile Systems. Russia with the help of Commonwealth of Independent States (CIS) countries is developing a comprehensive AD structure which could give depth to Russian Air space. THE AIR DEFENCE OF CHINA Armed with a formidable arsenal of nuclear weapons and rapidly maturing delivery capabilities, China has little to worry about in terms of major invasion. Since China is surrounded by potential adversaries, particularly the US Pacific Forces it deploys strong ground-based air-defenses to protect itself against sudden air attacks. The official terms for the PLAAFs AAA troops is gaoshepao bing/gaopaobing and the SAM troops is dikong daodan bing/didao bing/daodan bing. However, the PLAAF occasionally refers to its AAA troops as first artillery (yipao), and SAM troops as second artillery (erpao), which is often confused with Chinas Second Artillery Corps (erpao).  [21]   During the 1950s, the Soviets exported air defence equipment to China. But the Khrushchev-era tensions put an end to that, and over time China proceeded to reverse engineer all of these Soviet designs. On 6 February 1964, during his meeting with Dr Qian Xuesen (Father of Chinese Rocketry), Chairman Mao again expressed his views on the importance of the missile defence capability. According to Mao, missile defence capability should not be dominated by the two superpowers only, and China must also develop its own missile defence weapons, no matter how long it would take. This conversation, later known as 640 Directive, led to a missile defence system that could defend the country against nuclear-armed strategic missile attacks  [22]  . Early models SA-2 Guidelines from USSR were reverse engineered and entered service as the HQ-1 and soon after HQ-2 systems. Since the year 2000, HQ-2 remains a major cornerstone of Chinese air defenses  [23]  . In the 1960s-80s the main strategic adversary was USSR and consequently most air defenses are concentrated in the north of the country  [24]  . Chinese attempts at indigenous SAMs were somewhat poor even after an injection of Western technologies during the 1970s and 80s. In the 1990s and 2000s the focus had returned to the financial hub of Shanghai (and now Hong Kong) and the Taiwan Straits. PLAAF has upgraded its air defense (non-aircraft) capabilities which involves three of the PLAAFs branches: SAM, AAA, and radar troops. It is expending tremendous effort establishing an Integrated Air Defence System (IADS) at both the strategic (SADS) and tactical (TADS) levels.  [25]  SADS Integrates Naval, Space ABM TADS Integrates PLAAF PLA AD as explained in the figure below. The Automated Air Defense Command and Control System [IBACS] identifies targets, evaluates threats, allocates forces, and guides fighters. It also commands surface-to-air missiles (SAMs) and antiaircraft artillery (AAA), and it includes tactical air defense systems (TADS) and fixed radars. A sector operations center is linked with three TADS, various air bases, AAA sites, SAM units, radars, and ground and naval units  [26]  . Eqpt. REGIONAL AD FIELD AD FUTURE DEVP REMARKS HQ 9 (90KM/ 30KM)* TOR M1 ( SA-15) HQ -15 (SUPER S-300 )(200/25) *RANGE/ ALTITUDE SA-10 GRUMBLE (200/ 90) S-300 PMU HQ -7 (FM -80) HQ 16 (SUPER TOR M1 (35/20) HQ-12 KS 1(50/ 25) HQ 64 (LY -60) HQ 17 (30/17) HQ -2 B(90/20) QW-3/ TY-90 HQ 18 (400/35) PL-9/ HQ 61 A ABM SYS MANPADS ( QW  [27]  1,2,3 HN 5) QW [emailprotected] @ 4 TH GENERATION 14.5MM/ 23 MM/ 25MM/ 35 MM/ 57 MM/ 85MM GUNS. TYPE 95 GUN MISSILE SYSTEM GUN SYSTEMS The Chinese AD Doctrine post 2006 follows an Active AD Strategy with offensive and defensive character. Its deployment follows Three Strike or San Da concept which is a three ring layered deployment which is Key Area/ Key Point centric. Overall the countrys AD posture follows a front light and rear heavy pattern with institutionalized Passive Air Defence (PAD) measures. Despite significant improvement in military C4I, Chinese ability to control sophisticated military operations still lags behind current western standards and its varied AD equipment are yet to be battle tested. PAKISTAN Since most of our discussions all these years have been Pak centric, the readers would be familiar with its AD organization and setup. However, I wish to bring out certain salient aspects which are some recent developments:- Pak AD Studies (AADS 2000) and Study by HQ 4 AD Division in Jan 2008 has led to development of CLIAD (Comprehensive Layered Integrated Air Defence) Capability. This has ushered in era of variety of SAMs which are planned to be a mix of Western (30%) and Chinese (70%) equipment to be employed as under :- Combat Zone. It would primarily consist of RBS -70, FIM-90 (Chinese) and a variety of SHORADS (Short Range Air Defence Systems). Communication Zone. Low and Medium Altitude AD Systems (LOMAD) consisting of BAMSE (Sweden) and KS 2/ LY 60 D (China). Rear Areas. HIMADS comprising LD 2000 (China) and Phalanx (US). Both these systems are also capable of tackling all forms of missile threat. It has already authorized integral AD Regiments to its Infantry Artillery Divisions and is reorganizing the existing units to absorb new equipment thereby increasing the density of AD in Combat Zone. Redefining the Mission Of Army AD. Existing Mission. To provide ground based air defence to operationally critical assets/areas in harmony with visualized land air operations, nullifying or reducing the effectiveness of hostile air attacks and surveillance Redefined Mission . Provide AD cover against Low, Med and High alt air threat to national and tri Service VAsIVPs and field formations during defensive and offensive ops In the new mission Pakistan is not only looking to cover its air defence in all the spectrums but is also seeking for a better integration between the air defence forces with the other ground forces. Integrated AD concept implies provision of terminal def to PAF bases, CZ, VAs of national imp and create cone of AD wpns in specific areas of CZ in harmony with own air-land ops in order to cause max attrition on adversarys (Indian) air force.

Impact of a Jet

Impact Of a Jet Introduction: Over the years, engineers have found many ways to utilize the force that can be imparted by a jet of fluid on a surface diverting the flow. For example, the pelt on wheel has been used to make flour. Further more, the impulse turbine is still used in the first and sometimes in the second stages of steam turbine. Firemen make use of the kinetic energy stored in a jet to deliver water above the level in the nozzle to extinguish fires in high-rise buildings. Fluid jets are also used in industry for cutting metals and debarring.Many other applications of fluid jets can be cited which reveals their technological importance. This experiment aims at assessing the different forces exerted by the same water jet on a variety of geometrical different plates. The results obtained experimentally are to be compared with the ones inferred from theory through utilizing the applicable versions of the Bernoulli and momentum equations. Objectives: i. To measure the force p roduced by a jet on flat and curved surfaces. ii. To compare the experimental results with the theoretically calculated valuesProcedure: 1. Stand the apparatus on the hydraulic bench, with the drainpipe immediately above the hole leading to the weighing tank, see figure 4. Connect the bench supply hose to the inlet pipe on the apparatus, using a hose-clip to secure the connection. 2. Fit the flat plate to the apparatus. If the cup is fitted, remove it by undoing the retaining screw and lifting it out, complete with the loose cover plate. Take care not to drop the cup in the plastic cylinder. 3. Fit the cover plate over the stem of the flat plate and hold it in position below the beam.Screw in the retaining screw and tighten it. 4. Set the weigh-beam to its datum position. First set the jockey weight on the beam so that the datum groove is at zero on the scale, figure 5. Turn the adjusting nut, above the spring, until the grooves on the tally are in line with the top plate as shown i n figure 6. This indicates the datum position to which the beam must be returned, during the experiment, to measure the force produced by the jet. 5. Switch on the bench pump and open the bench supply valve to admit water to the apparatus.Check that the drainpipe is over the hole leading to the weighing tank. 6. Fully open the supply valve and slide the jockey weight along the beam until the tally returns to record the reading on the scale corresponding to the groove on the jockey weight. Measure the flow rate by limiting the collection of 8Kg of water in the bench-weighing bank. 7. Move the jockey weight inwards by 10 to 15cm and reduce the flow rate until the beam is approximately level. Set the beam to exactly the correct position (as indicated by the tally) by moving the jockey weight, and record the scale reading.Measure the flow rate. 8. Repeat step 6 until you have about 6 sets of readings over the range flow. For the last set, the jockey should be set at about 10cm from the zero position. At the lower flow rates you can reduce the mass of water collected in the weighing tank to 8Kg. 9. Switch off the bench pump and fit the hemispherical cup to the apparatus using the method in steps 2 and 3. Repeat step 4 to check the datum setting. 10. Repeat steps 5 to 9, but this time move the jockey in steps of about 25cm and take the last set of readings at about 20cm. 11.Switch of the bench pump and record the mass m of the jockey weight, the diameter d of the nozzle, and the distance s of the vanes from the outlet of the nozzle. Data and Results: Table 1: Results for Flat Plate Water Mass, Mw (KgTime, t (S)Distance, ?y (m)Mass Flow, m (Kg/s)Velocity, u (m/s) Initial Velocity, uo (m/s) Momentum, muo (N)Force on vane, F (N) 240. 560. 6642. 86546. 47545. 782342125. 89 240. 560. 6742. 86546. 47545. 782342126. 29 240. 560. 6442. 86546. 47545. 782342125. 89 240. 550. 6243. 64556. 41555. 7232425124. 32 241. 040. 5423. 08294. 27293. 581281121. 19 41. 380. 2317. 39221. 7 2221. 0496459. 025 Table 2: Results for Hemispherical Cup Water Mass, Mw (KgTime, t (S)Distance, ?y (m)Mass Flow, m (Kg/s)Velocity, u (m/s) Initial Velocity, uo (m/s) Momentum, muo (N)Force on vane, F (N) 240. 551. 3243. 63556. 28555. 5913334. 1652. 19 240. 561. 3242. 85546. 33545. 6413095. 3651. 79 240. 581. 3141. 38527. 59526. 9112645. 8451. 40 240. 591. 2840. 67518. 54517. 8512428. 4050. 23 241. 031. 1323. 30297. 08296. 397113. 3644. 34 241. 200. 7320. 00225224. 315383. 5128. 64 Calculations: 1. Mass flow rate, mf = mw / T In table 1: [ m= 24 / 0. 6= 42. 86 Kg/s] In table 2: [m=24 / 0. 55= 43. 63 Kg/s] 2. Velocity at nozzle exit, u= m / ? A , m = ? uA u= m / (1000 x78. 85Ãâ€"10^-6) u= 12. 75 x m In table 1: u= [12. 75 / 42. 86 = 546. 47m/s] In table 2: u= [12. 75 / 43. 63 = 556. 28m/s] 3. Velocity at impact with vane, uo: From Bernoulli’s equation: uo ^2 = u^2-2gs uo^2 = u^2 – (2 x 9. 81x 0. 035) In table 1: uo = [(v546. 78^2) – 0. 687] =545. 79 m/s In tabl e 2: uo = [(v556. 8^2) – 0. 687] =555. 59 m/s 4. Momentum flow in the jet at impact,J Moment,J = m x uo In table 1: [J= 42. 86 x 545. 78 = 23421 N] In table 2: [J=43. 63 x 555. 59 = 13334. 1N] 5. Force on vane F, F = (W x y) / 0. 15 In table 1: [F= (5. 89 x 0. 66) / 0. 15 =25. 89 N] In table 2: [F= (5. 89 x 1. 33) / 0. 15 =52. 19 N] 6. Slope of the graph, From flat plate graph, m m= (17500-10200) / (25-15) m= 730 From Hemispherical Cup graph, m m= (8500-6000) / (48-35) m=192. 30 Discussion . Turning the adjusting nut above the spring until the grooves on the tally are in the line with the top plate as shown in figure 6. 2. Recording the reading on the scale corresponding to the groove on the jockey weight. 3. Starting timer and adding weights when beam moves to horizontal. Stopping timer when beam moves to horizontal again. 4. The values of F theoretical (calculated from 4g? x) are close to those found experimentally. So we connect these points with a straight line. 5. Also f rom this graph we see that the calculated F (4g? ) is equal to the double of mu ? 2mu 6. It is clear from Fig that the force produced on each of the vanes is proportional to the momentum flow in the jet as it strikes the vane. From the data collected during the experiment, it is found that for different plate of vane used, the force exerted on the plate by the water will be different and it varies from flat and hemispherical plate. This is supported by the data of the column, distance of jockey from zero position which is the mean of knowing the force needed to balance the force exerted by the water. . We were to plot graphs of Force versus delivery of momentum for each plate on the same graph and we found the graphs posses different slope where the values are 2 and 1. 1 for hemispherical and flat plate respectively. We were able to plot the two plates on the same graph and although the relative slope is correct where hemispherical has the greater slope followed by flat plate, but t he calculation of the slope will not be correct because the value of x-axis is the same for all two graphs.So in order to obtain the correct value of slopes, the individual plotting of the graph has been plotted and the slope has been calculated. 8. When the water from the nozzle strikes the plate, it has the same initial velocity for the two plates but the velocity changes due to the obstruction by the plate and it will be different for each plate due to the geometrical effect. The geometry of the hemispherical plate minimizes the obstruction of the plate so the water will flow more freely relative to that of the flat plate.So, for the same flow rate, the hemispherical has a relatively higher final velocity than flat plate. Percentage of error of experiment: Accuracy = (muo-4g? X /4g? X) *100% For flat plate: (31. 20-1. 96/1. 96)=10. 2% (2. 10-1. 96/1. 96)=7. 14% (1. 73-1. 57/1. 57)=10. 2% (1. 35-1. 18/1. 18)=14. 4% (0. 9-0. 78/0. 78)=15. 4% Factor: Parallax error, during adjusting the level gauge to point, Water valve was not completely close and Press stopwatch start button late. For hemispherical cup: (4. 74-4. 1/4. 71)=0. 64% (4. 08-3. 92/3. 92)=4. 08% (3. 6-3. 14/3. 14)=14. 6% (2. 7-2. 35/2. 35)=14. 9% (1. 90-1. 57/1. 57)=21. 0% (0. 94-0. 78/0. 78)=20. 5% Factor: Parallax error, during adjusting the level gauge to point, Water valve was not completely close and Press stopwatch start button late. Question: Suggest two ways to improve accuracy of results? 1. It is by repeating the experiment a few times which make the results more reliable. 2. Measuring use highly precise digital measurement. 3.If the line didn’t pass through the origin that means that there is an error, because if the force is zero ( the jet doesn’t touch the vane) the should be placed at the origin which means ? y=0 so F=0 4. F = m (uo = u) u ? uo because we neglect reduction of speed so that u=uo fo = 2muo but the force on the hemispherical cup less than twice that on the flat plate. 5. The effect on the calculated force on the flat plate if the jet was assumed to leave the plate at 1? upward will be a moment in the x-direction which will decrease the moment in the y-direction F=m (1. 9uo) and it won’t effect the results too much. Conclusion As a conclusion, the experiment that have been carried out were successful, even though the data collected are a little bit difference compared to the theoretical value. The difference between the theoretical value and the actual value may mainly due to human and servicing factors such as parallax error. This error occur during observer captured the value of the water level. Besides that, error may occur during adjusting the level gauge to point at the white line on the side of the weight pan.Other than that, it also maybe because of the water valve. This error may occur because the water valve was not completely close during collecting the water. This may affect the time taken for the water to be collecte d. There are a lot of possibilities forth experiment will having an error. Therefore, the recommendation to overcome the error is ensure that the position of the observer’s eye must be 90 ° perpendicular to the reading or the position. Then, ensure that the apparatus functioning perfectly in order to get an accurate result.

Does Television Have Educational Value

Does television have educational value? Television, like anything else, has as much educational value as you allow it to. For example, television documentaries and sitcoms serve to reinforce or challenge societal norms and ideologies while reality television shows, in general, are intended to challenge long held beliefs and traditions. In contrast, Networks like as PBS and Nickelodeon educate young minds and the several hundred cable channels serve to support the education, whether easily apparent or trans[arentt, provided by the shows I've already mentioned as well as others.Therefore I would argue that television has significant educational value you only has to channel surf to se† that. It highly depends on what you watch. It used to be true that it had no educational value, when TV was nothing more than sit-coms and cartoons and soap operas. But, today you actually have educational options to television viewing. There's a number of different History channels, and The scienc e channel, just to name two that have very good, documentaries.News programming offers up political debates and commentaries, that we all need to hear and process. PBS has some good children's programming that teaches kids alot of valuable things. Personally I’d prefer to read than to learn anything from the television. Television focuses more on the visual aspect than the substantive. It pulls your mind in different directions. When you're reading, it's just you and the words, so I think you'd retain the material better than TV. It also depends on what you are watching and how much.I think if parents are afraid of their children watching too much television and not benefiting from it that they should monitor what their child watches. Make sure they know what the kid watches so that they know what the child is learning from it. Regulate television watching time and what is and what is not appropriate to watch. Watch together and talk about what the child watches and share the discussion. Most important of all, I think people should keep in mind that though television is tuned on for entertainment, it can also inform, enrich, and educate.

The Effect Of Bid Price Dispersion On Contracting ( Versus...

3.3 Effect of Bid Price Dispersion on Contracting (versus Contract Indecision) Due to the complex nature of IT services and the buyer’s lack of full knowledge of IT services, buyers in online labor markets face value uncertainty over how much to pay for an IT service in general (termed common value uncertainty) and how much to pay for the IT service from a particular freelancer (termed private value uncertainty). Because of the difficulty in assessing a freelancer’s true characteristics (e.g., skills, expertise, capacity, etc.), the buyer cannot precisely estimate the price of a particular freelancer for an IT service given his attributes (private value). However, it is feasible to infer the common value of an IT service based on the†¦show more content†¦Although the average of all freelancers’ bid prices, namely the estimate of the common value, is $80 in both scenarios, the dispersion in scenario (a) is larger than that in scenario (b). In scenario (b), all three freelancers bid a price very close to $80, which delivers a consist ent message to the buyer that the common value of the IT service is $80. Hence, the buyer is less uncertain to infer the common value as $80. In scenario (a), however, the three freelancers have very different bid prices, which makes a buyer more uncertain about the common value of the IT service ($80). In sum, a buyer will have higher (lower) common value uncertainty when bid price dispersion is high (low). We argue that the common value could serve as a practical benchmark to evaluate each freelancer’s bid price and infer how much more or less a buyer should pay a particular freelancer (to overcome private value uncertainty). Using our running example, in Scenario (a), the three bids’ prices ($40, $80, $120) are highly dispersed around the average of $80, and it will be very difficult for a buyer to evaluate any of these bids in terms of how much more or less she would need to pay a particular freelancer. Specifically, the lowest priced freelancer may deliver a low quality service, while the highest priced freelancer would reap the buyer’s potential surplus. In contrast, in Scenario (b) of the running