Physics 3A: Basic Physics I Shoup - Miderm Useful Equaions A y A sin A A A y an A y A A = A i + A y j + A z k A * B = A B cos(θ) A B = A B sin(θ) A * B = A B + A y B y + A z B z A B = (A y B z A z B y ) i + (A z B A B z )j + (A B y - A y B ) k v a d lim 0 f i v v v v d v d a v f lim 0 v f v i a v i d d a f i f i f i v a v i v f r i y j v f v i cos i consan v yf v i sin i g f i v i cos i y f y i v i cos i y f an i f R v i sin i g g v i cos i a r a c f v r F 0 F "! F F g m g T r v g a c h v PO ' v PO v O ' O F m a v r v i sin m m # g i a a a v d v d g $ 9.80 m% s $ 3.0 f% s Useful Consans
Physics 3A: Basic Physics I Shoup Miderm A - Soluions Name: Suden ID #: Discussion Secion: Dae: Signaure: (circle he leer of your answer). (5 ps) A paricle sars from res a he origin and hen moves along he -ais, iniially in he posiive direcion. Which of he following saemens can no be rue of he moion. a.) Is insananeous velociy a some poin is smaller han is average velociy. b.) Is insananeous velociy a some poin is larger han is average velociy. c.) Is average velociy is zero, while is insananeous velociy a some poins is nonzero d.) Is average velociy is zero and is insananeous acceleraion is always zero e.) A every poin in is moion, is insananeous velociy is equal o is average velociy. (5 ps) Vecor A =.0 i 3.00 j and vecor B = -4.00 i.00 j. Wha is he scalar produc of A and B? a.) 45.0 b.) -45.0 c.) 5.0 d.) -5.0 e.) none of he above 3. (5 ps) Two forces are acing on a rashcan wih a mass of 30.0 kg. The firs force is 0.0 N and he second force is 0.0 N. Wha is he magniude of he resuling acceleraion? a.).00 m/s b.) 0.33 m/s c.) 3.00 m/s d.) 0.738 m/s e.) no enough informaion o ell
4. (5 ps) You bes friend is abou o be eaen by a lion on he oher side of a wide, deep river. The speed of he river curren is 0.500 m/s. You are no a very fas swimmer and can only swim a 0.500 m/s, bu are an ecellen runner and can run a 0.0 m/s. To ge o your friend as quickly as possible, you should: a.) swim heading sraigh across he river b.) swim heading up river a an angle of 45 degrees wih respec o he bank c.) swim heading down river a an angle of 45 degrees wih respec o he bank d.) swim up river a 45 degrees for he firs half, hen down river a 45 degree for he second half e.) no enough informaion o ell 5. (5 ps) Bole A and bole B are boh launched separaely from a liquid nirogen cannon a an angle of 45 degrees above he horizonal. Bole B has wice he mass of bole A. If he pressure inside he cannon is he same when boh boles are launched, hen when hey each hi he ground, (ignore he heigh of he cannon, assume he acceleraion ime of boh boles are he same) a.) Bole A will have gone wice as far horizonally as bole B b.) Bole A will have gone half as far horizonally as bole B c.) Bole A will have gone four imes as far horizonally as bole B d.) Bole A will have gone one fourh as far horizonally as bole B e.) None of he above 6. (5 ps) Two ans are riding around in separae cars on a circular race rack. An Sam is driving a a consan speed of 00. m/s. An Jane is driving a a consan speed of 00. m/s. Which an eperiences he larger acceleraion and by how much? a.) An Sam's acceleraion is four imes as large as An Jane's b.) An Sam's acceleraion is wice as large as An Jane's c.) An Sam's acceleraion is half as large as An Jane's d.) An Sam's acceleraion is one fourh as large as An Jane's e.) Boh ans eperience he same acceleraion 7. (5 ps) If vecor C = A B, hen he scalar produc of A and C is a.) 0 b.) A * C c.) - A * C d.) A / C e.) none of he above
8. (5 ps) You hrow a ball sraigh up in he air and cach i when i comes back down. A wha poin in is moion is he magniude of is velociy he smalles? a.) Jus afer i leaves your hand. b.) When i reaches is highes poin. c.) Jus before i reurns o your hand. d.) The magniude of he ball's velociy does no change e.) none of he above 9. (5 ps) In he diagram below, wha is he magniude of he normal force of he able on block? roof a.) 0 N b.) 39. N c.) 9.6 N d.) 58.8 N e.) none of he above massless rope massless, fricionless pulley.00 kg 4.00 kg able 0.(5 ps) Your infiniely wise physics insrucor gives you a graph of he posiion of a yellow rubber duck versus ime and asks you o deermine he average velociy of he duck as i ravels from poin A o poin B. You correcly deermine his from he graph by a.) compuing he area under he secion of he graph beween poin A and poin B b.) drawing a line angen o he graph a poin A and compue he line's slope c.) drawing a line from he origin of he graph o poin B and compue he line's slope d.) drawing a line from poin A o poin B and compue he line's slope e.) elling your insrucor ha he average velociy can' be deermined from he graph.(5 ps) For a baseball baer o maimize he disance ha he ball will ravel horizonally, he mus hi he ball so ha he angle is iniial velociy makes wih he horizonal is a.) 75 degrees b.) 60 degrees c.) 45 degrees d.) 30 degrees e.) 5 degrees
.(5 ps) To impress your friends, you ell hem you can ell which of wo buildings is aller and by how much while blindfolded. You drop a ball from building A and you hear i hi he ground 3.00 s afer you drop i. You drop a ball from building B and you hear i hi he ground 6.00 s afer you drop i. The hen correcly ell your friends ha (ignore he ravel ime of he sounds) a.) building A is four imes as all as building B b.) building B is four imes as all as building A c.) building B is wice as all as building A d.) building A is wice as all as building B e.) none of he above
3.(0 ps) A block of wood wih a mass of.50 kg, saring from res slides down he fricionless incline plane in he figure below. I hen slides across he able where a consan force is applied on he block of 0.00 N oward he lef. a.) Draw a free body diagram of he block as i slides down he incline and anoher as i slides across he able. b.) Wha is he velociy of he block once i reaches he boom of he incline? c.) Does he block slide off he end of he able? If no, how far from he boom of he incline does i sop? (ignore effecs of when block moves from incline o able) (circle your final answers and show all work) y 0.750m 45 o.00m a.) N F=0.0 N N mg mg b.) F mg sin m a a g sin 9.80 sin 45 6.93 m s v f $ v i a $ 0 6.93 0.750% sin 45 $ 4.7 v f $ 4.7 $ 3.83 m % s c.) a $ F $ F $ m a F m $ 0.0.50 v f v f v i a no fall off. v i $ 3.3 m% s a 3.83 3.3 0.55 m since his is less han able lengh, i does
4.(0 ps) You jus changed your major a UCI o drama and have landed he par of Robin Hood in a local play. During he play you shoo an arrow a a arge which is 40.0 m away. You aim a he cener of he 5 cm diameer cenral circle of he arge and release he arrow. If he arrow is iniially flying horizonally, wha is he minimum velociy he arrow has o have so your arrow sicks wihin he cenral circle? (ignore air resisance) (circle your final answer and show all work) } y = radius of arge wan iniial speed, so use: f i v se iniial = 0. Need. use verical moion, compue how much ime o fall: y f y i se yf yi = dela y. Since iniially horizonal, hea = 0. so: y g v i y g 0.05 9.80 0.07 s 40.0 0.07 560 m s v i cos g