Deparmen of Physics College of Ars and Sciences American Universiy of Sharjah (AUS) Fall 014 Suggesed Pracice Problems (se #) for he Physics Placemen Tes This documen conains 5 suggesed problems ha are designed o help prospecive science and engineering sudens prepare for he physics placemen es. To adequaely measure readiness for he placemen es, hose 5 problems should be solved in NO MORE THAN 90 minues. 1) Suppose an equaion relaing posiion,, o ime,, is given by = b 3 + c 4, where b and c are consans and is meers and is in seconds. The unis of b and c respecively are; A) s 3, s 4. B) 1/s 3, 1/s 4. C) m/s 3, m/s 4. D) m s 3, m s 4. ) The densiy of aluminum is.70 g/cm 3 ; wha is he densiy of aluminum in kg/m 3? A).7 10 3 B).7 10-3 C).7 10 - D).7 10 3) Newon s law of universal graviaion is represened by m1m F G r where F is he graviaional force, m 1 and m are masses, r is he separaion beween he wo masses and G is force proporionaliy consan; re-arrange his equaion so as o epress r in erms of F, G, m 1 and m A) r Gm m / F. B) r Gm m / F. C) r F / Gm1 m. D) r F / Gm1m. 1 1
4) Which pair conains one vecor and one scalar quaniy? A) displacemen; acceleraion B) force; kineic energy C) momenum; velociy D) power; speed 5) A meal sphere of radius r (in meers) is released ino a ank of waer. As i sinks a speed v (in meers per second) i eperiences a drag force F (in Newons) given by F = krv, where k is a consan. Wha are he SI base unis of k? A) kg m s -1 B) kg m - s - C) kg m -1 s -1 D) kg m s - 6) A man ravels 30 % of he disance of his rip alone, hen walks anoher 1.5 km wih a friend and hen finishes he las half of he rip alone. Wha is he oal lengh of he rip? A) 5 km. B) 4.5 km. C) 7.5 km. D) 6 km. 7) A mooris drives norh for 36 minues a 85 km/h and hen sops for 4 minues. He hen coninues norh, raveling 13 km in h. Wha is average speed for he enire rip? A) 61 km/h B) 70.4 km/h C) 39 km/h D) 45 km/h 8) A car ravels norh a 50 km/h for 1 h. I hen ravels eas a 10 km/h for 1 h. Wha is he magniude of he car s average velociy for he rip? Norh A) 85 km/h B) 170 km/h Wes Eas C) 65 km/h D) 130 km/h Souh 9) The weigh of an objec is A) he same as is mass B) he force graviy acing on i C) dependen upon he velociy of an objec D) he difference beween graviaional aracion and air resisance 10) An objec of mass 10 kg is acceleraed downward a m/s. If g = 10 m/s, wha is he force of air resisance? A) 100 N upward B) 100 N downward
C) 80 N upward D) 10 N upward 11) If he lengh of a bo is reduced o one hird (1/3) of is original value and he widh and heigh are doubled (wo imes as much), by wha facor has he volume changed? A) 3/4 B) 4/3 C) 1 D) 1/3 1) An apple falls from a ree. Compare is kineic energy K o is poenial energy U. A) K increases and U decreases. B) K decreases and U decreases C) K increases and U increases D) K decreases and U increases 13) Two blocks are released from he op of a building. One falls sraigh down while he oher slides down a smooh ramp. If fricion is ignored, which one is moving faser when i reaches he boom? A) The block ha wen sraigh down. B) The block ha wen down he ramp. C) They boh will have he same speed. D) Insufficien informaion o work he problem. 14) Two cars raveling in opposie direcions pass each oher a 1:00 p.m. One of he cars ravels a a speed of 90 km/h, while he oher ravels a a speed of 7 km/h. How far apar will hey be a :00 p.m.? A) 16 km B) 108 km C) 144 km D) 180 km 15) The magniude and he direcion of he resulan force respecively are A) 110 N, 0 o, wih he + -ais B) 70 N, 90 o, wih he + -ais C) 50 N, 53.1 o, wih he + -ais D) 50 N, 36.9 o,wih he + -ais 0N 40N 50 N +y + 16) A mass acceleraes uniformly when he resulan force on i A) increases uniformly wih respec o ime B) is consan bu no zero C) is proporional o he displacemen from a fied poin D) is proporional o velociy
17) Neglecing air resisance, jus before i reaches he peak of he pah of is moion an objec hrown upward has A) is velociy direced upward and is acceleraion direced upward B) is velociy direced upward and is acceleraion direced downward C) is velociy direced downward and is acceleraion direced upward D) is velociy direced downward and is acceleraion direced downward 18) A rain slowly climbs a 500-m mounain rack which is a an angle of 10.0 wih respec o he horizonal. How much aliude does i gain? A) 86.8 m B) 88. m C) 341 m D) 49 m 19) A sone is hrown wih an iniial speed of 15 m/s a an angle of 53 above he horizonal from he op of a 35-m building. Wha is he magniude of he horizonal componen of velociy as he rock srikes he ground? A) 9 m/s B) 1 m/s C) 9 m/s D) 1 m/s 0) A faher pulls his young 40 kg daugher wih a force of 30 N a an angle of 30 o on a fricionless horizonal surface, as shown. Wha is he acceleraion of he bo? A) 0.75 m/s B) 1.33 m/s C) 0.65 m/s D) 0.375 m/s moion 30N 30 o Fig. 4-14, p.96 1) A 9:00 a.m., wo runners run owards each oher on a sraigh line wih consan speed of 4.5 m/s and 3.5 m/s, respecively, when hey are 100 m, as shown in he figure. How long will i ake for he runners o mee if hey mainain hese consan speeds? A) 5 s B) 1.5 s C) 6.5 s D) 11.1 s 4.5m/s 3.5m/s 9:00 a.m 9:00 a.m.
) Waer flows in a pipe (A) ha splis ino wo pipes (B and C). 5/8 of he waer goes ino pipe B, which hen splis ino pipes (D and E), wih D joining wih C o form he F pipe (see figure). If 3/5 of he waer in B wen ino D, deermine he percenage of he iniial waer ha ends up in he F pipe. A) 65 %. B) 6.5 %. C) 75 %. D) 77.5 %. F A B C D E 3) You have a machine which can accelerae a disk on fricionless ice. Saring from res, he disk ravels a disance in ime when force F is applied. If force 3F is applied, he disance he puck ravels in ime is A). B) 1.5. C) 4.5. D) 3. Quesions 4 and 5: The graph o he righ shows he velociy v of an objec moving in a sraigh line as a funcion of ime. v A) B) C) D)
4) Which graph correcly describes he disance raveled as a funcion of ime? A) Graph A B) Graph B C) Graph C D) Graph D 5) Which graph correcly describes he acceleraion of he objec as a funcion of ime? A) Graph A B) Graph B C) Graph C D) Graph D