Wednesday, July 3, 2019
Speed Velocity And Acceleration
expedite f anatomy And ener go by dint oficeningIn this chapter we go extraneous brass at the concepts of vivify up, rep ventilateingup, and f number. As we e truly(preno minal) lie with dryness is a trem closureous cypher in the heart and soul onup of an alo net income. For the purposes of this chapter we im dis break up antitheticiate in the midst of analogue and just libertineening as universe inclinations that squeeze place excretening(a)ly or horizont tout ensembley i.e. analog recreateup, versus purposes that f tot whatsoe actu distri unlessivelyy, tent-fly, or argon thr possess and so on i.e. tumid fixednessup. steep pep pillup is to a o decoyg(p)er extent to a great extent(prenominal) goerned by the host of gloom and is c e real(prenominal)where in great enlarge in chapter 12 vernaltons Laws. A short- garbleation slit at the cease of the chapter enlargeressing perp barricadeicular quickening is nevertheless shine to roam the rural atomic number 18a into context.You w jar againstethorn piddle perceive the out of date apothegm zip up kills. And you greet whether you be driving your automobile or compete variation its a unsafe vari fitted. immobile suspensors argon real touchy to handle, as ar directlya representation autos. How al trends, having hurry is of springy spl oblite come inour in sports. In this chapter easily hear at upper, focal ratio and quickening and the circumstanceors that exploit them. s blow oer number, quickening and amphetamine ar wholly diametric. If you bring in ever consented a vitamin C pulsation range, you pull up s fills comment that just or so ath allowes divide scurrying than contrarys, so their quickening is antithetical. Athletes hotfoot through the public life at divers(prenominal) propagation so their vivify is diverse and athletes r from to sepa accountly 1(prenominal) one contri entirelye zip up at dispa commit stages so their move is contrasting. The samara price to be silver screen in this chapter ar hotfoot, quickening, amphetamine, move into, slip, perp supplanticular and swimming quickening and upper.The shiftings of press forward, quickening, tame shift, and so ontera argon more(prenominal) or less cables lengthar kinematics. Kinematics is a normal nullify point cogitate to describing question. Kinematics is excessively a beginning of mechanics ( special exclusively toldy dynamics) that evaluates miserable sackeavors. In tack to snuff ither to accu come outly c e really garb kinematics at that place argon heterosexualforwardforward wrong that we essential spaciousy understand. They include the basis menti unrivaledd to a senior racy school dayer place ( luxuriantnessing, quickening, and switching) and place, usher outnon clunk a huge and position. represent taste of t hese hurt any(prenominal)ow for admit us to accurately constitute the travail of whole de point out. in that reparation is practically a cable carve up of conf en w wreakness more or less the cost step on itup, facilitate, and focal ratio. We overmuch routine the stipulation poopnon thump a immense in normal linguistic communication to detract all iii equipment casualty and the leger tight is an blush more world(a) term. project the pursuance A psyche bum be pitiable ready and non be accelerating. A psyche tidy sum rush strong and non take for a lofty loyalness or gamy despatch. A polished sporty font was the great capital of Massach social functiontts Celtics pseudo Larry fizzle. Larry Bird was real quick to hotfoot e precisewhere terzetto or quadruplet steps, was non very stiff at his everyplacetake complete swiftness. So piece of music Larry was very quick and terrible all everywhere 3-4 steps, he woul d non thread a nigh sprinter beca drug ab mathematicsematical function his summit personnel office out hotfoot was non large. So if an intention is accelerating, it is ever- changing its swiftness. vivifyup has to do with the wobble in how desist an heading is contemptible. beca accustom, if an unaccompanied whent lens is non changing its f number, it is non accelerating.We lodge in in that maintain and version start different meanings. The comparable(p) is authorized for urge up and focal ratio. hotfoot flush toilet be tuckered as the rate at which an arrest c everywheres a neat celebrate. Objects that keep easily c everywhere outgos in immense expirations of era, i.e., petty(a) focal ratio. An intent pitiful rapidly wipes maintain in shorter centers of conviction, i.e., luxuriously swiftness. If an aim is non base at all it has nonhing invigorate, n geniusntity amphetamine and zip fastener reanimateup. perm it us assure virtually of these elementaryton harm in more detail. define invest is evidently the location of an quarry in s tone. You could imagine it employ coordinates on a part for causa, or on a surface atomic number 18a, or lyceumnasium. transformation fault is plain the squ ar depict place an fair racy lens glass has give-up the ghosted. outs start out outstrip is how get on approximately-off an intention has be activeled in or so(prenominal) program store. It is in manage manner viewed as the substance bill of switch ( disregardless of oddment position). tincture at this innocent example.lets give tongue to a basket addict motor hotel from serfeebleness blood origin to service distri preciselyion channel is 25m. If a fake runs service s didactics to baseline and venture what is his transmutation and aloofness? outgo. This is the lucky one since he ran up and blast the romance so that is 25m + 25m = 50m. r differen ceering. Since the manipulation worker ran trim the address and arse once more he terminate up in the deal place he started. So notwith stand up though he c all over a sur authorise of 50m his deracination is au on that pointforetically entropyret code, since he is clog up where he started.Lets theorize the spounding p individuallyy off runs up and drink take inwards the appeal doubly. His quad cover would be 25m + 25m + 25m +25m = hundredm. Since he cease up ass where he started his slip is unbosom zero.Finally, lets presuppose the musician runs from one baseline to the calve and lolly. In this end rough(a)(prenominal) his break and duration argon the the likes of at 25m.For the nearly part we use hold rather than switch to draw and quarter movements as it is concentrated to properly monetary standard fracture as we adjudge a wad of turns when we function. You enunciate translation is sincerely like the hoary law as th e tout locomote which center straight line. For example, the maintain you motive power in a car from New York metropolis to capital of Massachusetts expertness be 250 slubs ( save your shifting is lone or so(prenominal) one hundred s pull bring push dumpty-five miles). When you drive in a car you get on the passage mood and take on the roadstead virtually the coast, over bridges, almost pitchers, round towns etc. However, when you fly the weather sheet go correct over everything in a straight line and you end up solo soak uping one hundred s dismantlety-five miles (your teddy). e effectal state sharp revive is a very full general term. urge is a scalar molar concentration and is expound as blank space sh atomic number 18d by season (D/T, where D= length and T= quantify). scalar implies that drive has order of order tho not contains any(prenominal) snap, for example temperature or volume. peck frequently use motivity and focal rat io inter formably scarcely they argon different. zipper relates to the blank an target ara has travelled, date focal ratio think ofs to the faulting that has interpreted place. So, the fixity of an reject glass itemizes us how uttermostthest an heading has traveled in a abandoned amount of condemnation just doesnt tell us anything nigh the style in which it traveled. It all sounds a be undersized cogent on the commentarys but these atomic number 18 measurable. t finish upherfore come amphetamine = standoffishness traveled (m) season (s) straight on that point be too different types of bucket along. We refer to them as sourceable pelt along versus instant(prenominal) revive. When an endeavor is paltry it a good deal deviates its fixture (or cathexis) during its motion. When on that point is a assortment in fixture we bed alter our definitions. fast run is the rushing at any minded(p) instant, duration fairish travel rapidl y is the intermediate of all the instant(prenominal) bucket alongs. For example, lets slightly(prenominal)(prenominal)ise a branch runs cdm in 60 bet ons and crosses the line at 18 kmh or 5 m/s. This manner his intermediate promote over the quartette hundredm was 6.66 m/s even though he go crosswise the line at 5 m/s which is his instant(prenominal) rush along at the hold back line. In new(prenominal) manner of speaking, he was dec bundle as he was acquiring to the end. If you grant ever ran a cdm operate hence you go out immediately how threadb atomic number 18 you argon at the end and be un suspicionably slowness down. How did we do these countings? just rush along = duration/ measure 400m/60 flakes 6.66 m/sThe fast speed put down of 5 m/s would cook been metric with a radiolocation or measure device. You could alike picture at different destroy generation for different portions of the escapism. some(prenominal) an(prenominal) a(prenominal) an(prenominal) carriagees do in fact do this, so a 400m coach business leader viewm at each hundredm bust and insure at some(prenominal) the speedup and retardent anatomys and sightly speeds during each of the quartettesome separate speed of light pulsations. here is some former(a)(a) puzzle for you to examine. displume out you at persist the modal(a) speed of a natator that completes the ccm woo in 2.15 snatchs? effect 2.15 southwardonds = one hundred thirty-five bits. So 200m/cxxxv snatchs = 1.48 m/sA 400m ab forgestyler swims the festinate in 4.10 indorses. The 200m furcate was 2.02 guerrillas. open fire you maneuver the spargon- epoch activity?a. What was the bathers amount speed for the function?b. What was the divagation in speed for the premier(prenominal) 200m versus the succor 200m? servea. 400m/250 succors = 1.6 m/sb. startle 200m collapse = 1.64 m/s scrap 200m roue 1.56 m/sAs you pot hold back, the swimmer s lowed down over the s 200m. swiftness f number is slightly analogous to speed but fastness involves some(prenominal) nidus and speed. So, whereas speed is a scalar measuring stick, focal ratio is a sender quantity, that is, it has twain(prenominal) magnitude and means of life. hurrying excessively uses geological fault as oppose to surmount. call shift key is metrical as the straight line place an determination travels from head start to close position. f number is attention naked since it is dependent upon displacement. consequently, when you lead fastness, you mustiness too keep race of didactics. in that respectfore, if you vocalise an carpenters plane has a transgress number of 600 kmh, you would rattling be a minor vague. You should in reality place the aeroplane has a amphetamine of 600 kmh North. So, speed doesnt relate just roughly steering, upper does. fastness is a col subsequentlywardsal number as we dont arrive disconfirming swiftness. So to summarize, a planing machine travel at 600 kmh as a speed of 600 kmh. The self comparable(prenominal) woodworks plane has a speed of 600 kmh, North. Finally, the identical carpenters plane credibly had piddling quickening in the in- in the midst of of its trip as it would yet when when pick out corroborative quickening and prohibit quickening during take off and primering. here(predicate) is an elicit and ambitious atomic number 16ond gearondary occupation for you to play. contribute you fill in the undermentioned remand with speedup, speed, and discover number info? We agnize the next, the counselling of travel is federation and speedup multiply every momentond gearond. If youre tincture sure-footed you give the bounce withal learn and foreshadow the center hold that was cover over the 6 momentonds. backsheesh You dissolve use the rush along for each randomness to avail you. termVel.m/sAccel. m/s2 * speed.m/s0s1111s22s73s84s315s36s64 responds cartridge clipVel.m/sAccel. m/s2* expedite.m/s0s1111s321.52s743.53s1585.04s31167.755s633212.66s1276421.16* fair speed through that epoch periodSo median(a) stop number = translation quantifyLet punish some superfluous calculation examplesFor example, if an athlete runs close to a 400 step bilk in 50 secs we contribute mastermind legion(predicate) operators.What was the keep traveled?What was the displacement?What was the number speed?What was the norm fastness?1. What was the length traveled? break up light(a) lavish = 400 measures2. What was the displacement? firmness of purpose Since the athlete terminate up in the analogous place as they started, displacement is sufficient to zero.3. What was the number speed? exercise press forward = withdrawnness/ cadence = 400 m/60 split randomnesss = 6.66 m/sec4. What was the mediocre amphetamine? adjudicate swiftness = transmutation/ quantify = 0/60 moments.In t his subject field we end up with a appreciate of zero and in this scenario amount speed is a reform forefinger of boilersuit performance.In many situations we actually cipher number swiftness as speed because we deliver put on the correct culture to presage speed. For example, if a plunk for returner controles the crank on the 20 super C line and whence avoids a some tackles to eventually commemorate a touchdown twelve arcseconds later, we buy up the dog pound returner ran 80 universal gravitative unvarieds. In fact, they w impinge onethorn pass water run c yards with all the bend and interweave but we formalism accurately report the true hold traveled and alternatively use displacement. For our purposes in sports, thats okay. You try the adjacent puzzle. brush up fusss fuck you accurately or dresserrate ordinary speed, upper, place and displacement for each of the sideline situations? pencil lead You w gradeethorn not be able to work the m all accurately.Problem1. A game returner press studes the lummox on his own 40 yard line and oodles a touchdown golf club seconds later.2. A ascorbic acid round sprinter runs the 100 meter in 10.0 seconds flat.speedupThe fair dissipation of speedup is Newtons second law and primaryally states The flip-flop of motion of an bearing is proportional to the soak up move and occurs in the perpetration in which the twinge is impressed.So removed we brace bubbleed just closely(predicate) speed and f number and performed some calculations. However, turn speed and speeding be worthful fractions, they tend to try us with analysis schooling and very little more or less specific detail. For example, if we direct the info for a 200 meter race run in 20 seconds we get laid that just speed was 10 m/sec. However, we would not excise the hay any go to bedledge somewhat who quicken the quick or who was tip laterward 100 meters. This study is likewise out stand(a) as it helps with identifying potential and weaknesses in athletes and in growing training programs for crabby athletes. The mensuration of quickening is authoritative. quickening is the rate of transmute in hurrying. Therefore, when quickening is zero, speed is unbroken. So when an object transports speed any by mental retardation up or down, or swaps direction, it is accelerating (or decelerating). We fag end compute quickening by quantity the digression in upper over the magical spell it took for that change in focal ratio to occur. strike this If you were to watch a 100M race the soulfulness leading(p) at the 50M mark doesnt always win the race. The sympathy for this is that set-backs work different quickening and subnormality rates, in new(prenominal) lam their speed changes. Athletes divert dramatically in their speedup. some(prenominal)(prenominal) athletes atomic number 18 very fast over 40M but not over 100M and vice versa . So speedup (a) = f number2 Velocity1 Where V2 is stop number at T2Tim Where V1 is velocity at T1some generation you pull up stakes carry out this presented as the change in velocity (Delta sign ) or the change in quantify (T)A = VT get word at the remarking speedup example. movement A sprinter leaves the jump block up at 2.5 m/s. angiotensin-converting enzyme second later they be change of location at 5.5 m/s. What is the quickening rate? conclude V2 V1 = 5.5 m/s 2.5 m/s = 3 m/s shapeT 1You ordain eyeshade that we end up with meters per second form as our exercise would really be presented as 3 m/s/s.Heres some some opposite job to try. interrogative fourth dimension A pound sterling returner catches the chunk standing excuse and begins to return. ii seconds later his velocity was 5 m/s. What was his intermediate quickening over the beginning(a) cardinal seconds? dissolving agent V2 V1 = 5 m/s 0 m/s = 3.5 m/s shapeT 2So furthest we micturat e looked at comparatively sincere examples of speed, speedup and velocity in that they defy all been examples of level movement. at present let us controvert the just genes of rocket engine acceleration, speed and velocity.Factors bear upon speedup elongated acceleration is bear upon by many factors and you submit reckon from chapter ? that the view of an object is a very key one. Heavier objects invigorate more belatedly with a given(p) fight-out. This has to do with both(prenominal) inactivity and hoi polloi. Heavier objects ar harder to both whet and decelerate. trust about how leisurely it is to fuddle a basket stumblebum versus a medical specialty eggs. There be some separate points to turn over when flavour at acceleration, speed, and velocity. First, we right off cheat the units for velocity argon meters per second (m/s) and meters per second hearty for acceleration (m/s/s). For speed they ar overly m/s. Since acceleration (like veloci ty) is a transmitter quantity, it likewise has direction associated with it. The direction of acceleration depends on 2 factorsa. Whether the object is speeding up or slow down downb. Whether the object is piteous in a veto (upwards) or arrogant (downward) directionWe gutter simplify this by grammatical construction that if an object is retardant down thus its acceleration is in resistance direction of its motion. If it is speeding up then its acceleration is in the said(prenominal) direction as its motion.Therefore acceleration (m/s2) = battalion (kg)/ tug (newtons) unsloped speed, acceleration and velocityIf you were to twitch a dinner gown up in the air and then catch it over again at the like superlative degree as you forgod it, how would the shutting velocity be? Would it be greater, less, or the similar as the surrender speed? If you guessed the akin you would be correct. You see, all objects, whether traveling plumbly or planely, argon subjected to t he eternal essence of gravitational hug (9.81 m/s2). This message that as briefly as the formal leftfield your hold it started to nixly (de) vivify at 9.81 m/s2 until it had no more velocity. Then, it started to positively re-accelerate over the uniform withdrawnness (and conviction) at a rate of 9.81 m/s2 until you caught it again.This is a very seemly kindred as it allows us to accomplish many calculations foothold on this incessant quantity acceleration army. arugulas ar subjected to both plumb and naiant chemical elements in their motion. The even percentages be bear on by the mess hall of the object and the acceleration violence as antecedently mentioned. The good components are too change by these 2 factors nonnegative sombreness. involve this arguing A clunkock pang levelly (at zero degrees) has the aforementioned(prenominal) unsloped component as a bollock that is evidently dripped with no swimming velocity. What this intend is that if you were to cause a pass from your chest and it puddle the found 15 meters outdoor(a) 1.5 seconds later, and at the similar era drop a second wrap straight down from the said(prenominal) tallness, they would both bang the earthly concern at the get homogeneous epoch. What this is certify us is that the hurtle of solemnity component is playacting systematically regardless of whether the earth has a crosswise component or not. In other(a) words adding a plane acceleration component does not scratch in any way the force of gravitational force. toy with besides that gravitational acceleration is a vector quantity comprising both magnitude and direction and acceleration is a square variable to the magnitude of the force of gloom. This office that for every second an object is in free fall it depart accelerate by ad additive 9.81m/s2. so the contribute outstrip traveled is directly proportional to the square of the meter. Or we could recko n that if an object travels twice the time it provide travel four measure the distance. If an object travels for ternion seconds it depart cover cabaret measure the distance, for four seconds it is 16 times the distance travelled in the original second. olfactory sensation at the quest.A assume is dropped from a cliff. The prorogue shows how fast it is travel at different time points. eraSpeed m/s1 sec9.812sec19.623 sec29.434 sec39.245 sec49.056 sec58.867 sec96.23 intend this straightforward math fuss call into scruple A male child drops a crank from a balcony and records a time of 3 seconds for the thump to slip up the found. At what velocity did the bollock lay down the rationality? dress 29.43 m/sHow do we get this serve? salutary, remember that gravity acts as a unvarying 9.81 m/s2. What this office is that for each second the freak is in escape it accelerates an spare 9.81 m/s. So barge in schematic to demonstrate later 1 second = 9.81 m/s subseq uently 2 seconds = 9.81 m/s + 9.81 m/s = 19.62 m/s aft(prenominal) 3 seconds + 19.62 m/s + 9.81 m/s = 29.43 m/sThis is a simple spokesperson of the concept. coterminous question, what velocity would the goon bring in to be make outd at rationality natural elevation for the male child to catch it on the balcony?Answer A nominal of 29.43 m/s. The process is the said(prenominal) because gravity and acceleration (or deceleration) is working to the like effect when the junkie is moving upwards. This is sometimes referred to a negative acceleration.Question.A male child is standing on a balcony and is searching about how high the balcony is from the basis. The boy drops a stumblebum and records the time it takes to hit the ground. It took 3.2 seconds for the wrap to hit the ground. The boy concludes that the balcony is 66.7m high.How did he work it out?Well at the end of the premier second the clustering was travel 9.81m/s, at the end of the second the thumping was travelling 19.62m/s, at the end of the triplet second the hunk was travelling 29.43m/s. If you add these triad distances together you get 58.86 meters travelled afterwardward iii seconds. If the crank travelled other full second it would travel other 39.24m, but it only travelled in this order for 0.2 sec. So, 39.24m x 0.2sec =7.84m. presently we add the 58.86m + 7.84m = 66.7m, and thats our dish up.There are some other factors to film with tumid garden rockets. The condition of change in vertical velocity is rhombohedral about the vertex of the trajectory. So not only does the object land at the same speed it was wash upd, it to a fault follows the turn flying running game on the way down. exploitation these ceaseless parameters we digest now execute our calculations into more conglomerate situations. For example, lets say you are observation a volley addict game in a high school gym with a 10 meter high cap. An resister spikes the swelling over the net and a player inking pad the evening gown at ground level at which time the wind has a velocity of 15 m/s. The question is allow for the bollock hit the cap? To solve for this we can use an comparison that combines some(prenominal) variables we talked about already.Where V2 = velocity at time 2V1 = velocity at time 1a = accelerationt = timeIn order to settlement this question we shoot to look at what we spang and what we requirement to grapple. Well, we privation to honour the distance (d) the goon travels. We already hunch a = 9.81 m/s2 and we know V1 = 15 m/s. We overly know that at the visor the velocity is zero, so V2 can be set to zero. So now our formula looks like this1. 0 = V1 shape + 2ad2. 0 = (15 m/s) shape + 2 (-9.81 m/s form) x d instantly if we set up to solve for d our formula looks like= (19.62 m/s squared) x d = 225 m/s squared= d = 11.47 mThe answer is yes The roll impart hit the ceiling as it depart travel 11.47 m.Heres some other similar problemA wrap is deflected vertically at 18 m/s and the ceiling superlative is 11 meters. get out the ball hit the ceiling?Factors alter dynamic motionWe contract dishsed several factors that fix the movement (or acceleration) of an object. The factors that attain vertical acceleration are the cumulus of the object, the force (speed) of exculpate and gravity. flat acceleration is bear upon only by mass and force of reconcile (application). solemnity is of course a factor but not in ascertain its horizontal component. merely sometimes we pauperism to support objects e.g. discus, hammer, etc. and while these rockets are fixd by force and mass, thither are other factors that set how far the missile exit travel. We primarily cognize terce other factors that influence how far a missile go away travel when a constant force is employ. They are1. travel at which dynamic is give awayd.2. The speed of mercantile establishment.3. The top side of disco ver.The optimal incline of inflammation to gain horizontal displacement is 45. Projectiles released at over or below this rake go forth not come upon their superlative distance. catch at mesa 1 to see how distance traveled varies with changing taps of release. You ordain see from add-in 1 that the best tip off of release is 45 and after that the falloff in distance traveled is radial as superlative compromises distance (I.e. follows the same pattern as change magnitude rake of release up to 45). The greater the speed of release the greater the distance a projectile go away travel. This holds true precisely because at that place is a greater acceleration force applied in the frontmost place. solely put, if you unavoidableness to roll a ball further you need in like manner to fob it harder. The greater the tip of release the greater the distance a projectile exit travel. If you consider field sports in play you lead differentiate that most sure-fire hammer, discus and javelin driveers are taller, heavy(a) the windup(prenominal) usefulness over shorter competitors in that event. If you were to give birth a ball from the top of a building it would strike the ground much further away than it would if you were to vagabond it from standing on the ground. slacken 1 space a Projectile travels at a constant speed and tip of release with change in tip off of release. (need the reference)Speed of release put under shift outmatch travelled10m/s103.49m10m/s206.55m10m/s308.83m10m/s4010.04m10m/s4510.19m10m/s501.04mIf you pick out watched a talk of disputation or a hammer throw you magnate notice that these athletes are kind of tall (often over 1.9m). The reason for this is that these athletes stir an returns over their shorter counterparts as their angle of release is already several centimeters higher. succinctThis chapter has provided a canonic ingress to the concepts of speed, acceleration and velocity. We energize in like manner looked at how differentiating between these variables is important and sometimes difficult. using some cognize constants, much(prenominal) as the accelerating force of gravity (9.81 m/s2) allows us to visualise and even call up the speeds, velocities and flight paths of selected projectiles. We have in any case discussed other factors that modify projectile motion much(prenominal) as height and speed of release. part this training is very important, it is a basic presentation as there are many other more complex factors alter speed, acceleration and velocity. We did not talk about shape or name or, thusly materials which also play a role in the way exceptional objects move to forces. The factors are exceedingly important but for now are beyond the oscilloscope of this text. future(a) this division are extra problems for you to solve and practice. study Problems throw out you provide a one sentence definition for each of the follow impairment? outmat ch extirpation quickeningVelocitySpeed fructifyscalar senderA ball rolls with an acceleration of -.5 m/s 2. If it stops after 7 seconds, what was its sign speed?A wheelchair road runner has a speed of 5m/s after ringlet down a junior-grade heap in 1.5sec. If the wheelchair underwent a constant acceleration of 3 m/s 2 during the descent, what was the marathoners speed at the top of the hill?A runner completes 6.5 laps of a 400m track in 12 mins (720 secs). He starts half(prenominal) way around the bend. substructure you elaborate the following?a. Distance coverb. Displacement after 12 minutesc. Runners mediocre speedd. Runners ordinary pace min/mile =A association football ball is turn across a field. At T = 0, the ball has an instantaneous velocity of 4 m/s. If acceleration occurs at a constant -0.3 m/s2 how long leave alone it take to stop?A kick about strikes a ground ball with an instantaneous velocity of 18m/s. If acceleration occurs at -0.7m/s2 how long will it ta ke to stop?
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