力學 救救我 謝謝！（第三題不用）

1. Considerathin rod ofuniform linear mass density pL with mass 4/ and length /, find the gravitational potential。dp/有)。at a perpendicular distance Afrom the center ofthe rod. You may find the integral in (E.6) in Appendix E useful 2. A spherical planet of radius 人> consists ofacore of radius 有/ with uniform density pi. and a thick outer cloud of dust with umiform density p: Find the force (magnitude and direction) onamass箇inside the dust cloud ata position ARp from the planetcenter( 吃<訪<記), 3. Use Fermat's principle by applying calculus of variation to minimize the time oflight passing from medium ofrefractive index jg, to another medium ofrefractive index >, derive the Snells law ofrefraction: js光 名2s 銷 4. Consider the Atwood machine oftwo masses connected by amassless string oflength 7overapulley ofradius gas shown, (a) Write down the total kinetic energy and potential energy in terms of the coordinatex Hence obtain the Lagrangian ofthe system. (b) Derive the Lagrange's equation of motion and hence find the acceleration ofthe masses. x 和二 工

大一普物 請問第9題要怎麼寫

區9. 10. 一 六 余 條 監工 選hor A basketbal] player is 15 了 horizontally from the center Qf the basket, which is 10 ft off the ground. At whatangb should the player aim the ball from aheight of8.2 ft with a Speed of 26人/s? A diyer leaves a 3-m board on a trajectory that takes her 2.5 m above the board and then into the water 2.8m horizontally from the end ofthe board. At whatspeeil and angle did she leave the board? 半生 (3) Show 也at 了e position of a particle on a circle_ of radius AR With its center at the Orlgin 1S 7三[cos +sin9史, where 幻 is the angle the position vector makes with thex-axis. (b) IFthe partlcle Inoves With constant speed y Starting on 了he x-aXis at /三0, find an expression for 9 interms oftime / and the period 7to complete a full circle. (c) Find the magnitude and direction ofthe aeeeleration.

求第17題

人 14. Profit The profit 16. 人2/ 2 / Wcd/e Figure for 17 Figure for 18 18. 95 。Volume_AIl edgaes of a cube Pro hom selling x units Of a product ls glven by 2三 510N 0 atarate ot 9 units per dl the prottt when (am) 、 二 4 The sales are Jncreasing ay. Find the rate Of change Of 00 units and (bD)文三 600 unjts, qre expanding at a rate How fast is the volume changing when each edge is (a) 2 centimeters and (b) 10 centimeters? ot 6 centimeters per second, Surface Area_AI edges ofacube are expanding at a Tate of 6 centimeters Per Second. How fast is the surface area changing when each edge is (a) 2 centimeters and (b) 10 centimeters? 。 Boating_A boat is pulled by a winch on a dock, and te winch is 3 meters above the deck of the boat (See figure). The winch pulls_the Tope at arate of 1 meter per second. Find thexspeed 6fthe boat when 5 meters 9t Tope 1S out. What happens to the Speed of the boat as it gets closer and closer to the dock? Shadow Length “Aman 2meters tall walks at arate 0f ].5 meters per second away from a light that is 5 meters aboye the ground (see figure). | (a) When he js 3 meters from the base of the light, at 人 和 生0) what rate js the tip of his shadow moving。 (b) When he js 3 meters from the base of the at what rate js the Jength of his shadow changlng。 Air Traffic_Control An airplane flying at an altitude Of 10 kilometers pasSes directly over aradar 蟬戰品 品 figure). When the airplane is 26 kilometerS away ($ 三 26), 由 卅0 ee 21, 22 23 24 12 店

請問句末的reservoir effect是儲庫效應嗎？（Fig1） 是的話，請幫我繼續解答🙏 有一個含萃取物凝膠，塗抹在皮膚上，滲透係數Kp 較低，但是滯留時間Lag time很長，所以文章解釋為reservoir effect儲庫效應，我看了一下參考文獻(fig2)，但... 繼續閱讀

The HPLC analysis ofthe last samples colleceted in the permeation assays allowed to caleulate the percentage ofbioactive compounds that permeated through the biologieal barrier after 24 hours as well as their permeation fluxes, expressed as hg em? hi (Table 3). Asp-eoumarie acid and caffeic acid are slightly lipophilic, iis possible that, even 放 they did not manage to pass the s/rgjo corjezo, they were trapped in the human membrane, happening whatitis called “Teservoir effee 六

一直算都錯😖，求解

Problem: relative to 丸 Is om always smaller than zz, larger than we orthe same Ph as uu, or does it have sorme other shed k 中 Telationship? COTn- TeaS,。 (4 Lisa rushes down onto a subway 7? 1the Platform to find her train already 主 leparting. She stops and watches b the cars go by. Fach car is 8.60 m ( 語 long. The first moves past her in 站 1.50 sand the second in 1.10 5. 實 Find the constant acceleratlion Of 時 則 thetralin. With )eSlt CHALLENGE PROBLEMS np lt hes is 42. Two thin rods are fastened to ~e on the inside of a cCircular TIng as shown in Figure P2.42. One rod of length Dis vertical, and 17th the other of lenoth 了 makes an

33題，有人可以幫我列算式就好嗎 是波氏分配（卜瓦松分配）題目

CHMAPTER 6 smen er replacem es, muff plecitlons w 1r 同 the numper oftransmissf sen0C7 polsson 昌關 dmwpute 4 o Shop. The! te dett Ave/lino's Aut 字 ee 3 stributlon le butlon ls the an summary, the Polsson dis 呈ty dlstob n summar OP 4 needed to construct a Poiss 4 on aa random variable, desl9! errors, or other r: ellhood t 的 elikeli nedthejkelJncoo 同 on nsurance Company ge 1 polic surar From actuary taples, Washington 2 gten nsurance aty 』 age 25 wi qie within the next year is pay ity they wi 25-year-ojg men this year' whatis the probabilty 3 JjnaPoisson distributionn 三0.4 a. What is the probapility thatx三0 b. What is the probability thatx > 0? 32. 全a Poisson distributionh 二4 a. What is the probapbility thatx 三 2? b. What js the probapbiljty thatx 生 2? f experience, c. What js the probability thatx> 2? m her years ol 還 officer at Coast Bank and Trust. Fro ble to repay 9 inot bea she estimates that the probability is .025 that an applicant wi hs or her jnstajiment loan. Last month she made 40 1 父 What js the probability that three loans will be 和 sfaulted? 紀 What js the probability that at least three loans will be del tthe rate oftwo per Automobijles arrive at the Elkhart exit ofthe Indiana Tol 同 ibution minute. Tne distribution of arrivals approximates a Poisson distri 了人 a.- What is fhe Probabifity that no automopbiles arrive in a particular uiar Pp. what js fhe Propabjlity that at least one automobile arrives during mrnute? 5 站5 estimated that 0.5% ofthe Callers to the Customer Service department of Dell Jnc. wil receive a busy signal. whatis the probability that oftoday's 1,200 callers at reast 5 received a Pbusy signal? 。 生如e past schools jn Los Angeles Couni year for weafher enmergencies. What is 1 Counfy wi close for 4 days next year? 24 ty have closed an average of 3 days each he probability that schools in Los Angeles opapjlity distribution js a !ting apjjty associated wjth each Out( discrete propapjjity distribution can aSsume only certain values. The main features are: _The sum offhes probabilties is 1.00. The probapijlity ofa particular outcome is between 0.00 and 1.00. Jheoutcomes are mutually exclusive. ontinuous djsfribution can assume an jmfnite number ofvalues within a speecsi iean and variance ofa probability distribution are Computed as follows, mean js equalto: Come- ific rang variance js egqual to:

想請問第一題的d小題

be 說 he 三 中 49,799 Thursday 1.515 Friday 2.26042(32,857) 74,271 Saturday 0.40104(32,857) 13177 | Total 230,000 d. The federal government threatens to withhold Sevenil for Denver, Colorado. The acceptable visibility standard hundred million dollars in Department of Transnr is 100, with readings above 100 indicating clean air tion funds unless Denver meets visibility audan and good visibility, and readings below 100 indicating within 8 years. HOW would you proceedl to ii temperature inversions caused by forest fires, volcanic aj7ong-fern judgment forecast of technologies 人 will be available to improve visibility in the next 10 years7 2. Kay and Miehael Passe publish ngf's 妃qppenjnge一 biweekly newspaper to publicize local events. hots 1as few subseribers; typically is s0ld Mueh ofthe revenue comes from Wand supermarkot specials,h assoeiated With printing t00 | them to the wrong location Iterized system to ol S aeeurately Tec0it She system was imhple diIY derlined. Selln 1. Figure 8.9 shows summer air visibility measurements

求圈起來的幾題

補史名www asftrppfysfts 600) For Thoughtand Diseussion tneuish the Aristotelian and Galilean/Newtonian views ofihe ball bounees ofrawall with the same speedithad beforeithit Wall Has its momentum changed? Hasaforoe acted on the 2 Has aforee acted on the wall? Relate your answers to New aws of motion ten use the term "inertias to deseribe human sluggishness 5this usage related to the meaning ofFsinertiae in physics? does aceiling fan continue to rotate even after you have vitched it ofP? Wek erashes into a Stalled cear A student trying to explain the es ofthis event claims thar no forees are involved: the car Tin the way”so itgot hit Commen foot astronaut kicks a ball, hard, across aspace station balls apparent weightlessness mean he astronauts toes 下avity on Jupiters moon Io is one-fifth that on Would happen te your weight and to your mass if nIo? tis the direcetion of momentum oFamoving body? Does it Fthe body: plane aceelerates down the munway, you take your keys r poeket and suspend them by a thread. Do they hang force from the chairon you. iir? Hnot, what forees are fxerrisesaned Problems 85 $ 還2620Groeoeoeardaoeos WiA poaor Wonoeno0 Op ir oa 20。 Staring frorm rest and undergoing constan acceleratiom,a920-kg ar covers 410 min $.15 8. Find the foree on the car 21 dropping dontest, a student encatses am 83-g cgg in large Styrofoam block. fs g emn'texceed 2.0N and 計the bloek hits the g pow mueh must the Styror jompress on impaet) Note: The aceelei assoeialed with stOppi gravity while the Styrofe the ground. 22. Inatront-end collision, a 1400-kg car with shockzabsorbing bump: ems can withstand amaximum force of 75kN before damage Gccurs: Hthe maximum speed foranondamaging collision is 9.0 kmzh, by Bow much must he bumper be able to move relative to the car? section 4.4 The Force ofGravity 23。 Show that the units of aceeleration can be written as N/kg- Why doesitmake sense to give gas 9.8 N/kg when talking about imass and weight? 24. Your spaceship crashes on one of the Sun's planets, Fortunately 上 the ship's scales are intact and show that your weightis 680 N.H your mass is 58 kg, where are you? (imr: Consult AppendixEE) Your friend can barely lift a 35-kg concrete block on E: massive ablock could she lift on the Moon? 26 Acereal box says "net weight 350 grams” Whats the actual Weight ta in SLunits and (b) in ounees? 27. Youre asafety engineerforabridge spanning the U,S-Canadian border. U.S. speeifications permit a maximum load of 10 tons What load iimit should you speeify on the Canadian side. where welght is given in kilograms? 28.。 The gravitational acceleration atthe lntermational Space Stations altitude is about 91凶 oFits surface value. Whats the weightofa 64-kg astronaut atthis altitude? ection 4.5 Using Newton's SecondLaw A 50-kg parachutist deseends atasteady 40 km/h. What foree does air exert on the parachute? 30, A 960-kg motorboat accelerates away from adock at2.1 m/s Its propellerprovides a3.9-kN thrust force. What drag force does the water exert on the boat? An elevator aceelerates downward at2.4 ms. What force does the elevator's floor exertona52-kg passengery 32. At 560 metric tons, the Airbus A-380 is the World's largest air- liner Whats the upward force on an A-380 when the plane is (am flying at constant altitude and (b) aceelerating upward at 15m/s2? 33. Yourre an engineer working on Ares 1 NASAs replacement tor the space Shuttles. Performance speces call for afirst-stage TOcket Gapable ofaccelerating atotal mass 0f 600 Me vertically ftom Testt0 7700 km in 1.7 min. Youre asked to determine tbe re- quired engine thrust (force) and the foree exerted ona79-kg as- tronaut during Tiftoff. What do you Teport? 34. You step into an elevatorand itacceleratesto adownward speed gfF8.8 mAS in 2.4 5 Quantitatively compare your apparent weight during thistime with youracetual weight, 44.6 NewtonsThirdLaw ional foree does 3 5600-kg elephant exer 必 63. she jumps ofta140-emhi過台 人 rdheras she falls?

4.59答案為什麼是a

mass, are 「 PASSAGE PROBLEMS 了 R/S BODY. Dancers experience jjmps they make. Tor example Speed7 sma- jZOnta] ) case7? he box )n foT 7 ere no an en- )1S at- 了1S and 1S Ve Up- glvVen 「graph 1 TV planet, when a dancef ]an head by 過e neck cause 負e head to $ 9g.4% of atypical personsm Janding after a Vertical Jump $ 4.0 m/s to restinatime of 0.20 S. 4,57 What 1$ the magnitude Of the average force that her neck exerts on her head during the ]anding? (3) ON; (b) 6O N; (c) 120 N: must exceed the jow down and come to Tes- The head is about as8. Video analysis ot a 65-kg dancer hows that her head decelerates from hthe force her neck exerts on her head during the ]anding, the force her head exerts On her neck 1S (3) the Sames: (b) greater; (co) smaller: (d) greater during the first half ot the land- uring the second halt of the ]anding. 4.,58 Compared Wit 9 and smaller d 4,59 While the dancer 1S in the air and holding a fixed bose what is the magnitude of the force her neck exertS On her heady (3 ON; (b) 6O N; (o]) 120 N; (0) 180 N. 4.60 The forces ona dancer can be measSsured directly When a dancer performs aJump On a force plate that measSures the 10rfce betWween her feet and the ground. A graph Of force verSus time es a Vertical jump performed on aforce plate is Shown lt es at 1S happening at 0.4 $? The dancer is (3) bendlng 0 1S acceleratling downward; (b) pushtung er legs and is almost ready to leave the ground (o in the air and at the to have just touched the 一 her jump; (d) landing and her feel Figure P4.60

我們將真菌 TCU970 的 lipase 以 PCR 放大後接進細菌用 expression vector 裡，再放進大腸桿菌裡表現。這套系統已被證實可以表現各種細菌 DNA 來大量製造蛋白質，但我都無法讓細菌大量製造這個酵素。請列舉我在哪些可能出問題及如何驗證。