Phys101 Second Major-061 Zero Version Coordinator: AbdelMonem Saturday, December 09, 2006 Page: 1

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1 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: Q. A 6 kg crate falls frm rest frm a height f.0 m nt a spring scale with a spring cnstant f N/m. Find the maximum distance the spring is cmpressed. A) 40 cm B).0 cm C) 60 cm D) 7.0 cm E) 5.0 cm Q. A 4.0 kg cart starts up an incline with a speed f 3.0 m/s and cmes t rest.0 m up the incline. The net wrk dne n the cart is: A) -8 J B) 8.0 J C) - J D) 6.0 J E) -0 J Q3. A net hrizntal frce f 50 N is acting n a.0 kg crate that starts frm rest n a hrizntal frictinless surface. At the instant the bject has traveled.0 m, the rate at which this net frce ding wrk is: A) 500 W B) 5 W C) 75 W D) 00 W E).5 W Q4. At time t = 0 a single frce ( F ) acts n a.0 kg particle and changes its velcity frm ˆ ˆ v = (4.0i 3.0 j) m / s at t = 0 t v = (4.0iˆ+ 3.0 jˆ) m / s at t = 3.0 s. During this time the wrk i dne by A) 0 B) 6.0 J C).0 J D) 50 J E) 0 J F n the particle is: f c-0-n-0-s-0-e--fg--f-0

2 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: Q5. A. kg blck starts frm rest n a rugh inclined plane that makes an angle f 5 with the hrizntal. The cefficient f kinetic frictin is 0.5. As the blck slides.0 m dwn the plane, the mechanical energy f the Earth-blck system changes by: A) 9.8 J B) 0 J C) 9.8 J D) 8 J E) J Q6. An ideal spring with a 0 N/m spring cnstant is cmpressed by a 0 N frce. The ptential energy stred in the spring is: A).5 J B) 0.50 J C) 5.0 J D) 0 J E) 00 J Q7. An bject f mass m, attached t a light crd f length L, is held hrizntally frm a fixed supprt as shwn in Fig. The bject is then released frm rest. What is the tensin frce in the crd when the bject is at the lwest pint f its swing? Fig# A) 3 mg B) mg C) mg D) mg / E) mgl Q8. A blck f mass.0 kg is initially mving t the right n a hrizntal frictinless surface at a speed 5.0 m/s. It then cmpresses a spring f spring cnstant 00 N/m. At the instant when c-0-n-0-s-0-e--fg--f-0

3 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: 3 the kinetic energy f the blck is equal t the ptential energy f the spring, the spring is cmpressed a distance f: A) 0.50 m B) 0.5 m C).0 m D) 0.75 m E) 0.0 m Q9. Tw identical 500 kg cars are mving perpendicular t each ther. One mves with a speed f 5 m/s due nrth and the ther mves at 5 m/s due east. What is the ttal mmentum f the system? A) 4.4 x0 4 kg m/s at 59 Nrth f East B) 4.4 x0 4 kg m/s at 3 Nrth f East C) 6.0 x 0 4 kg m/s at 3 Nrth f East D) 6.0 x 0 4 kg m/s at 59 Nrth f East E) 4.0 x0 4 kg m/s at 59 Nrth f East Q0. A small bject with linear mmentum 5.0 kg m/s makes a head-n cllisin with a large bject at rest. The small bject bunces straight back with a mmentum f magnitude 4.0 kg m/s. What is the magnitude f the change in mmentum f the large bject? A) 9.0 kg m/s B) 5.0 kg m/s C) 4.0 kg m/s D).0 kg m/s E) 3.0 kg m/s Q. A 500 kg car traveling at 90.0 km/h east cllides with a 3000 kg car traveling at 60.0 km/h suth. The tw cars stick tgether after the cllisin (see Fig ). What is the speed f the cars after cllisin? Fig# A) 3.9 m/s c-0-n-0-s-0-e--fg--f-0

4 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: 4 B) 8.33 m/s C) 7.4 m/s D).7 m/s E) 50.0 m/s Q. A 3.0 kg mass is psitined at (0, 8.0) m, and a.0 kg mass is psitined at (, 0) m. What are the crdinates f a 4.0 kg mass which will result in the center f mass f the system f three masses being lcated at the rigin (0, 0)? A) (-3.0, -6.0) m B) (-, -8.0) m C) (3.0, 6.0) m D) (-6.0, -3.0) m E) (-, 0) m Q3. A string (ne end attached t the ceiling) is wund arund a unifrm slid cylinder f mass M =.0 kg and radius R = 0 cm (see Fig 3). The cylinder starts falling frm rest as the string unwinds. The linear acceleratin f the cylinder is: Fig# 3 A) 6.5 m/s B) 9.8 m/s C) 3. m/s D) 4.9 m/s E). m/s Q4. A 6 kg blck is attached t a crd that is wund arund the rim f a flywheel f radius 0.0 m and hangs vertically, as shwn in Fig 4. The rtatinal inertia f the flywheel is 0.50 kg m. When the blck is released and the crd unwinds, the acceleratin f the blck is: Fig# 4 c-0-n-0-s-0-e--fg--f-0

5 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: 5 A) 5.5 m/s B).5 m/s C) 8. m/s D) 9.8 m/s E) 3 m/s Q5. A particle f mass 0.50 kg is attached t ne end f a.0 m lng rd f mass 3.0 kg (Fig 5). The rd and the particle are rtating arund the ther pivted end f the rd with.0 rad/s. The kinetic energy f the system abut the pivt is: Fig# 5 A) 3.0 J B) 0.84 J C) 0.50 J D) 0.6 J E).0 J Q6. A disk starts frm rest and rtates arund a fixed axis, subject t a cnstant net trque. The wrk dne by the trque during the time interval frm t = 0 t s is W and the wrk dne during the time interval frm t = 0 t 6 s is W. The ratiw /W = A) 9 B) 3 C) / 3 D) / 9 E) 4 c-0-n-0-s-0-e--fg--f-0

6 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: 6 Q7. A particle, held by a string whse ther end is attached t a fixed pint C, mves in a circle n a hrizntal frictinless surface. If the string is cut, the angular mmentum f the particle abut the pint C: A) des nt change B) changes directin but nt magnitude C) increases D) decreases E) becmes zer Q8. What is the net trque abut the rigin n an bject lcated at (0, -5.0, 5.0) m when frces F = 3.0kˆ and F =.0 jˆ N act n the bject? ( ) N ( ) A) ( 5.0iˆ ) N m B) ( 0 jˆ ) N m C) ( 5iˆ ) N m D) ( 3.0 ˆ.0 ˆ) E) Zer k + j N m Q9. A thin unifrm rd f mass M = 3.0 kg and length L =.0 m is suspended vertically frm a frictinless pivt at its upper end. An bject f mass m = 500 g, traveling hrizntally with a speed v = 45 m/s strikes the rd at its center f mass and sticks there (See Fig 6). What is the angular velcity f the system just after the cllisin? Fig# 6 A) 5.0 rad/s B). rad/s C) 4.3 rad/s D) 3.7 rad/s E) 0.57 rad/s c-0-n-0-s-0-e--fg--f-0

7 Crdinatr: AbdelMnem Saturday, December 09, 006 Page: 7 Q0. A thin hp rlls withut sliding alng the flr. The rati f its translatinal kinetic energy f the center f mass t its rtatinal kinetic energy abut an axis thrugh its center f mass is: A) B) C) 3 D) 4 E) ½ c-0-n-0-s-0-e--fg--f-0

8 PHYS-0 Frmula Sheet fr the Secnd Majr Exam (06) r r = v t+ at v = v + at ( ) ( ) v = v + a x x x x = v+ v t dp F = ma = ; p = mv f = µ N k k fs µ sn W = F dr W = F d if F is a cnstant A B = A B csθ A B = A B sinθ W net = K = mv f mv dw P = = F v U = kx, F = kx U s g = mgy Emech = K + U U = W fr a cnservative frce K + U + E = W where Eth = fkd J = F = Favg t = p p + p = p + p i i f f th s i F ext = Macm n r cm = mr i i = rdm M M i= m m m v = v + v f i i m+ m m+ m m m m v = v + v f i i m+ m m+ m dθ dω ω = ; α = s= rθ, v = rω v at = rα; ar = = rω r a = a + a ; a = a + a t r t r If α is cnstant : ω = ω + αt θ θ = ω + α t t ( ) ω = ω + α θ θ I = mr = r dm i i i Ip = Icm + Mh τ = r F τ = rf sinθ = r F = rft W = τdθ = τ θ if τ is cnstant l = r p = mr v l = mr v= mrv Fr a slid rtating abut a fixed axis : K, rt = Iω L z = I ( ωf ωi ) K = I = W dw P = = τω dl τ = dl τext = = Iα ω x d x dx = ; ( t ) = nt n + n + n n n g = 9.80 m/ s I ( ) cm cylinder = MR I ( ) cm slid sphere = 5 MR I ( ) cm thin rd = ML I (, ) cm ring abut central axis = MR I (, ) cm ring abut diameter = MR