Physics 180A Fall 2008 Tes 1-120 poins Name Provide he bes answer o he following quesions and problems. Wach your sig figs. 1) The number of meaningful digis in a number is called he number of. When numbers are muiplied or divided, he number of hese digis in he resul is no han he in he facor wih he of hese. When you, he answer can have no more decimal places han he erm wih he decimal places. (4 ps) a) significan digis, greaer, mos, add or subrac, fewes b) significan digis, leas, fewes, muliply or divide, leas c) precision figures, greaer, mos, muliply or divide, leas d) significan digis, greaer, fewes, add or subrac, fewes 2) In everyday usage, we ofen use he word model...in physics, a model is a version of a physical sysem ha would be oo o analyze in full wihou he. (4 ps) a) small, messy, smallness b) represenaive, large, complicaions c) complicaed, simplisic, complicaions d) simplified, complicaed, simplificaions 3) Complee he calculaions by using he prefies of he unis. (6 ps) 1) femo Tera = 2) milli / nano = 3) Giga micro = 4) Mega / micro = 5) 10 9 10 7 = 6) 10 3 / 10-6 = 4) How all is a flagpole, if I am sanding 30 meers from he base of he pole and sighing he op wih a proracor a an angle of 43? (4 ps) 5) How many sig figs does each number conain? (4 ps) 1) 0.002 2) 2000 3) 2.02 10-6 4) 1.025600 5) 21500 6) 7000 billion 7) 700 10 9 8) 0.0000500 6) Trigonomery is he mahemaics ha deals wih he of he of he sides of a righ riangle. The sides have names: he which is opposie / he hypoenuse, he cosine which is he / by he hypoenuse and he angen which is he / he adjacen. (4 ps) a) lenghs, raios, sine, opposie, adjacen b) lenghs, raios, sine, adjacen, opposie c) raios, lenghs, sine, hypoenuse, adjacen d) raios, lenghs, sine, adjacen, opposie 7) Do he calculaions (wach your sig figs) (3 ps) 1) sin 66.3 = 2) an -1 (43/34) = 3) 1750 sin 40 =
8) Wha do he wo slopes represen on he graph? (4ps) a) b) 9) If vecor B has componens B and B y and makes an angle θ wih he -ais, hen (4 ps) a) θ = B y /B b) an θ = B /B y c) B = B + B y (where B is he magniude of B d) B cos i = B 2 2 + B y 10) Draw he velociy and acceleraion graphs associaed wih he displacemen graphs. (6 ps) a) v v v a a a 11) A wildebees is running in a sraigh line, which we shall call he -ais, wih he posiive direcion o he righ. The figure below shows his animal's velociy as a funcion of ime. (4 ps) Which of he following saemens abou he animal's moion mus be rue? A. I is moving o he lef beween a and b and o he righ beween b and c. B. I is moving o he righ beween a and c. C. Is speed is decreasing from a o b and increasing from b o c. D. Is acceleraion is increasing
12) Fill in he diagram. (6 ps) a) Which cars are speeding up or slowing down? b) Wha are he signs of he acceleraion in each siuaion? c) Wha is he overall equaion ha deermines he sign of he accleraion? 13) The key o analyzing is he fac ha we can rea he and y coordinaes. So we can hink of his moion as a combinaion of moion wih consan velociy and verical moion wih. (4 ps) a) projecile moion, separaely, horizonal, consan velociy b) projecile moion, separaely, horizonal, consan acceleraion c) freefall moion, ogeher, verical, consan acceleraion d) projecile moion, ogeher, horizonal, consan acceleraion 14) Wrie he wo moion equaions ha describe he wo pahs in he diagram. (4 ps) a) b) 15) Why does he arrow hi he apple? (3 ps) a) The archer aimed he arrow a he poin a which hey will collide. b) he apple is falling faser in he y-direcion bu he arrow is raveling in he -direcion faser. c) boh he arrow and h apple are falling a he same rae. d) boh he arrow and he apple have he same horizonal velociy. 16) A brick is released wih no iniial speed from he roof of a building and srikes he ground in 3.30 s, encounering no appreciable air drag. How all, in meers, is he building? How fas is he brick moving jus before i reaches he ground? (6 ps) all fas
17) A ennis ball rolls off he edge of a ableop 0.850 m above he floor and srikes he floor a a poin 1.90 m horizonally from he edge of he able. Find he ime of fligh of he ball. Find he magniude of he iniial velociy of he ball. Find he magniude of he velociy of he ball jus before i srikes he floor. (9 ps) v o V f 18) A golf ball is hi ino he air, bu no sraigh up, and encouners no significan air resisance. Which saemens accuraely describe is moion while i is in he air? (4 ps) a) Is horizonal velociy does no change once i is in he air, bu is verical velociy does change. b) Is verical acceleraion is zero a he highes poin. c) On he way up i is acceleraing upward, and on he way down i is acceleraing downward. d) On he way up, boh is horizonal and verical velociy componens are decreasing; on he way down, hey are boh increasing. 19) Draw he freebody diagram for each objec in each figure ne o he figure in he siuaions below. (6 ps)
20) A person pushes wo boes wih a horizonal 100 N force on a fricionless floor, as shown in he figure. Bo A is heavier han bo B. Which of he following saemens abou hese boes is correc? (4 ps) a) Boes A and B push on each oher wih equal forces of less han 100 N. b) Bo A pushes on bo B wih a force of 100 N, and bo B pushes on bo A wih a force of 100 N. c) Bo A pushes on bo B harder han bo B pushes on bo A. d) The boes will no begin o move unless he oal weigh of he wo boes is less han 100 N. 21) Three books are a res on a horizonal able, as shown in he figure. The ne force on he middle book is (4 ps) a) 5 N downward b) 0 N c) 15 N upward d) 15 N downward 22) 23) A block of mass m = 3.00 kg is released from res h = 0.600 m from he surface of a able, a he op of a θ = 40.0 incline. The fricionless incline is fied on a able of heigh H = 4.00 m. (4 ps) (a) Deermine he acceleraion of he block as i slides down he incline. (b) Wha is he velociy of he block as i leaves he incline? (c) How far from he able will he block hi he floor? (d) How much ime has elapsed beween when he block is released and when i his he floor?
24) DRS Problem. Draw a Diagram (5ps), Reason your seps (5ps) and Solve he problem (5ps).