A.P. Physics B Uni 1 Tes Reiew Physics Basics, Moemen, and Vecors Chapers 1-3 * In sudying for your es, make sure o sudy his reiew shee along wih your quizzes and homework assignmens. Muliple Choice Reiew: On his porion of he es, you will no be allowed o use your calculaor or AP formula shee. (You may, howeer, use your AP able of informaion.) Approimae g=1m/s for simpliciy of calculaions. No parial credi will be gien. 1. Wha is he magniude of he elociy afer 1.5 seconds of a ball hrown upward from a heigh of 5m a 4m/s? a. 15m/s b. m/s c. 5m/s d. 3m/s e. 35m/s. For an objec ha raels km norh and hen 15km souh, wha is he raio of he disance raeled o he displacemen? a. b. 1/7 c. 1 d. 7 e. 35 3. Two ecors A and B boh hae magniudes of 5 unis. The magniude of he ecor sum of hese wo ecors... a. is 5 unis. b. is 1 unis. c. is unis. d. could be answer a or b, bu no answer c. e. could be answer a, b, or c. 4. An objec is hrown wih a horizonal elociy of m/s from a cliff ha is 15m aboe ground leel. If air resisance is negligible, he ime ha i akes he objec o fall o he ground from he cliff is mos nearly a. 3s b. 5s c. 6s d. 1s e. 5s 5. The rae of change of elociy is he definiion of... a. displacemen c. insananeous elociy b. aerage elociy d. acceleraion
6. Three balls are projeced from he edge of a cliff. Ball I is fired horizonally, ball II is fired a an angle of 3 o aboe he horizonal wih he same speed as ball I, and ball III is released from res. Which one of he following is rue? a. I and II hi a he same ime, and III his laer. b. I and II hi a he same ime, and III his earlier. c. I and III hi a he same ime, and II his laer. d. I and III hi a he same ime, and II his earlier. e. All hree balls hi a he same ime. 7. A rock is hrown horizonally off a building. The speed of he rock as i leaes he hrower s hand a he edge of he building is. I akes an amoun of ime,, o rael from he edge of he building o he ground. How far from he side of he building, measured horizonally, does he rock land? a. g b. g c. d. g 8. An objec is hrown sraigh upward. Which of he following are he correc signs of he elociy and acceleraion ecors a he momen he objec is a is highes poin? Velociy Acceleraion a. + - b. + c. - d. - e. 9. A spacecraf has one engine a is ail, which can propel i forward a 4m/s, as well as sabilizing engines on eiher side, each of which can propel he craf a 3m/s perpendicular o he direcion of he ail engine s propulsion. If one of he side engines and he rear engine are simulaneously operaing, a wha angle will he craf rael relaie o forward? a. 3 o b. 37 o c. 45 o d. 53 o e. 6 o 14 1. A he highes poin of is rajecory, a projecile fired a 3 o aboe he horizonal from a saring heigh of m... a. is insananeously a res. b. has raeled half he disance o is impac poin. c. has acceleraion. d. has a horizonal elociy componen equal o is iniial alue. e. has more han one of he aboe properies.
Problem Reiew: On his porion of he es, you may use your calculaor, AP formula shee, and AP able of informaion. Parial credi will be gien on hese problems. 11. A rock is hrown sraigh downward a 1m/s from a heigh of 3.5 m. How long does i ake he rock o reach he ground? 1. Skech graphs of he following siuaions, firs on posiion-ime graphs and hen on elociy-ime graphs. a. Slowing down a a consan rae. b. Speeding up a a consan rae. c. Siing sill a a posiie posiion. d. Moing a a consan pos. elociy. a. b. a. b. c. d. c. d. 13. Two cars are in a race, wih Car A driing a an aerage speed of 7mi/h and Car B driing a an aerage speed of 65mi/h. How long does he race ake if i ends (when Car A crosses he finish-line) wih Car A 1/4 mile in fron of Car B?
14. A ruck on a sraigh road sars from res acceleraing a 3.m / s unil i reaches a speed of 3. m/s. I hen applies is brakes and comes o a sop in 8. s. Wha oal disance does he ruck coer during he oal period of moion described here? 15. The engine of a model rocke acceleraes he rocke upward erically. The rocke sars from res and i acceleraes upward a 5 m / s unil is engines sop afer 4.1 s. Wha is he maimum heigh he rocke reaches? 16. A car akes a rip where here are wo differen displacemens inoled. The o car firs raels for h a a elociy of 6 km/h a 7 norh of eas. I hen urns and raels for 3.1h a a elociy of 93km/h a o norh of wes. Wha is he car s resulan displacemen? 17. A ball is hrown upward a an angle of 5 o aboe he horizonal. I passes is maimum heigh, hen srikes a wall 3m away from is saring posiion a a heigh of 1m aboe is saring heigh. Wha was he ball s iniial elociy?
18. A sone is kicked horizonally from he edge of a cliff wih an iniial elociy of 3 m/s, and i lands on a fla, horizonal beach 7 m (measured horizonally) from he cliff wall. How far aboe he beach is he cliff? Wih wha speed and angle of impac does he sone land? 19. Acual A.P. Physics B Free-Response Quesion (): A.5kg car moes on a sraigh horizonal rack. The graph of elociy ersus ime for he car is gien below. (m/s) 1.8.6.4. -. -.4 -.6 -.8-1 -1. 5 1 15 5 (s) a. Indicae eery ime for which he car is a res. b. Indicae eery ime ineral for which he speed (magniude of elociy) of he car is increasing.
c. Deermine he horizonal posiion of he car a =9.s if he car is locaed a =.m a =. d. Skech an acceleraion ersus ime graph for he moion of he car from = o =5s. e. From =5s unil he car reaches he end of he rack, he car coninues wih consan horizonal elociy. The car hen leaes he end of he rack and his he floor, which is.4m below he rack. Neglecing air resisance, deermine each of following: i. The ime from when he car leaes he rack unil i firs his he floor. ii. The horizonal disance from he end of he rack o he poin a which he car firs his he floor.
Uni 1 Tes Reiew Answers: 1. C (I slows down by 1m/s eery second, so in 1.5s i has slowed by 15 m/s.). D (Disance = 35km and displacemen = 5km, so 35/5 = 7.) 3. E (Depending on he orienaion of he wo ecors, ABC are all possible.) 4. B (The approimaion is = 5, so 15 = 5 leads o = 5s.) 5. D 6. C (Balls I and II boh begin wih y = m/s, so hey boh hi a same ime.) 7. C (Horizonal elociy is no conrolled by g, he acceleraion due o graiy.) 8. D (= a highes poin, acceleraion is always -9.8m/s.) 9. B (Jus ake an -1 (3/4) o find θ. Noice ha he green shee has helpful geomery and rig info.) 1. D 11. 1 Using = + a we hae - 3.5 = ( 1) 4.9. We use he quadraic formula o arrie a he answer =.35s. 1. a. b. a. b. c. d. c. d. 13. A = 7 and B = 65 and also, A = B and A = B +. 5 A B B +.5 B Since A = B hen = and = 7 65 7 65 3.5 B = 3.5mi so he race ook ime B = =.5h or 3 minues. 65 14. In par I we use = + a o hae 3 = + (3) so = 15m. formulas. In par II we don' know acceleraion, which we need for using any of our So we hae o find accel. by using he definiion of acceleraion. - 3 1 a = = 3.75m/ s Now use = + a = 3(8) + 8 for par II of he rip. Lasly, = 15 + 1 = 7m. oal 1 ( 3.75)(8 ) = 1m
15. 1 In he powered par of he rocke's fligh, we use = + a o hae 1 = + (5)(4.1 ) = 4.3m and = a 5(4.1).5m / s. + = + = Once he engine sops, we use = + a o hae =.5 19.6, which yields = 1.44m. So, he ma heigh of he rocke is 4.3 + 1.44 = 63.47m. 16. Sar by urning i ino a displacemen problem insead of a elociy problem. Then i becomes a 4-Sep Addiion problem. oal = 88.3cos6-1cos7 = 13.11km y oal = 1sin7 + 88.3sin6 = 36.44km R = + y = 376.8km @ θ = an -1 (y/) = 74.1 o θ 17. = gies 3 = o cos5 Also, y = yo + 1/a gies 1 = o sin5-4.9 Now ha s a sysem of equaions w/wo unknowns. Sole for o = 36.7m/s 18. = gies 7 = 3 which makes =.33s so y = 4.9 = - 4.9(.33 ) = 6.6m, he heigh of he cliff. y Also, for elociy and angle of impac : y = y g =.87, which is no he oal final speed. Taking boh elociy componens ino accoun yields he -1.87 o following: = y + = 3 +.87 = 37.7m/ s @ θ = an = 37.3 3 19.a. On a / graph, an objec is sopped anyime =, or when he graph crosses he -ais. This happens wice in his graph- a =4s and =18s. b. The speed is increasing anyime he signs of he el and accel are he same sign. So his happens on he graph from = 4 o 9s (when and a are boh negaie), and from = 18s o s (when and a are boh posiie). c. To use a kinemaic o calculae posiion of he car, we would firs hae o know he acceleraion of he car during he ineral = o 9s. Acceleraion is jus slope = -.m/s. Then use = o + a which gies (-1) =.8 + (-.) and his gies = -.9m. I is lasly imporan o remember ha he in he aboe kinemaic refers o a change in posiion, so we mus calculae final posiion based on he car s iniial posiion being.m. So final posiion is. -.9 = 1.1m d. To come up wih he correc graph, jus calculae he car s acceleraion during each ime ineral by finding slope of each par of he firs graph. e.i. In he erical direcion, y = yo + 1/a so -.4 = -4.9 so =.86s ii. In he horizonal direcion, = = (.8)(.86) =.9m θ