Phys101 Final Code: 1 Term: 132 Wednesday, May 21, 2014 Page: 1

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1 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 1 Q1. A car accelerates at.0 m/s alng a straight rad. It passes tw marks that are 0 m apart at times t = 4.0 s and t = 5.0 s. Find the car s velcity at t = 0. A) 1 m/s B) 4 m/s C) 16 m/s D) 11 m/s E) 48 m/s x 5 x 4 = v 4 t + 1 at 0 = v 4 (1) + 1 ()(1) v 4 = 9m/s 9 = v 0 + a(4) v 0 = 1 m/s Q. Q. Tw vectrs are given by A = 1.00ˆ i +.00 ˆj and B = 1.00ˆ i +.00 ˆj. Find the angle that the vectr A B makes with the psitive y-axis. A) 166 B) 100 C) 1 D) 111 E) 17 C = A B = ı 4ȷ tan 1 θ = 1 4 θ = 14 Angle frm y axis = = 166 A prjectile s launch speed is 4 times its speed at maximum height. Find the launch angle frm the hrizntal. A) 75.5 B) 70.6 C) 45. D).0 E) 49. At maximum height v y = 0 v = v x = v 0x v 0 = 4 v 0x v 0 = 4v 0 csθ 0 θ = 75.5

2 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: Q4. Q5. A particle mves at cnstant speed in a circular path. The instantaneus velcity and instantaneus acceleratin vectrs are bth: A) Perpendicular t each ther B) Perpendicular t the circular path C) tangent t the circular path D) Oppsite t each ther E) Parallel t each ther In unifrm circular mtin, the acceleratin is perpendicular t velcity at each instant. An elevatr initially mving upward is slwing dwn at a rate f 1.50 m/s. If the tensin in the cable is.0 10 N then find the weight f the elevatr. A) N 4 B) N 5 C) N D) N E) N T W = ma W = T + mg a g W = T. 10 = 1 a/g = N 9.8 Q6. A 1 N hrizntal frce is applied t a 4.1 kg blck initially at rest n a rugh hrizntal surface. If the cefficients f frictin are µ s = 0.5 and µ k = 0.4. Find the magnitude f the frictinal frce n the blck. A) 1 N B) 16 N C) 10 N D) 0 N E) 8.0 N f smax = µ s F n = µ s mg = (0.5)(4.1)(9.8) = 0.1 N F < f smax N mtin f s F = 1 N

3 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: Q7. A single frce F acts n a blck f mass m =.0 kg frm t = 0 s t t = 4.0 s. If the psitin f the blck is given by x = t 5. t then find the wrk dne n the blck by F. A).7 10 J B) J C) J D) J E) J v = dx dt = t 5. v(4) = 4.8 m/s; v(0) = 5. m/s W = K = 1 m(v 4 v 0 ) = 707. J =.7 10 J Q8. Q9. The Rtatinal inertia f an bject des nt depend upn: A) Its angular velcity. B) Its mass. C) Its size and shape. D) The lcatin f the axis f rtatin. E) The distributin f its mass. I is independent f L A unifrm meter stick pivted at 10.0 cm mark is scillating. Find the perid f scillatin. A) 1.57 s B). s C).60 s D) 4.15 s E).4 s T = π I 1 mgh = π 1 ml + mh m(9.8)(0.4) 1 = π m 1 + (0.4) = 1.57 s m(9.8)(0.4)

4 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 4 Q10. A thin unifrm rd f length 1.5 m and mass 0.50 kg is suspended freely frm ne end. It is pulled t ne side and then allwed t swing like a pendulum, passing thrugh its lwest psitin with angular speed 5.0 rad/s. Neglecting frictin and air resistance, find the rd s kinetic energy at its lwest psitin. A) 4.7 J B) 1. J C) 9.4 J D) 0.90 J E) 7.8 J K = 1 Iw = 1 1 ml w = 1 6 ml w = 1 6 (0.5)(1.5) (5) K = 4.7 J Q11. A frce f magnitude 10.0 N acts n a rigid bdy. The frce lies in the xy plane. Its line f actin passes thrugh the pint (0.500, 0.00) and makes an angle f 0.0 with the psitive x-axis. Find the trque f the frce abut the pint (-0.00, 0.00). A) kˆ (N.m) F B) 4.00 kˆ ( (N.m) C) kˆ ( (N.m) D) 1.00 kˆ ( (N.m) r 0 F E) î ( (N.m) τ = r F sin0 = (0.8)(10) 1 = 4.00 k (N. m)

5 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 5 Q1. A hrizntal unifrm beam f weight 1000 N is supprted by a hinge at ne end and by a cable at the ther end, as shwn in Figure 1. Find the magnitude f the frce exerted n the beam by the hinge. A) 1000 N B) 100 N C) N D) 1500 N E) 89.0 N F v Figure 1 T 0ᴼ Στ = 0 F n W W L = TL 1 T = W = 1000 N ΣF x = 0 F n = Tcsθ (1000) cs(0) = N ΣF y = 0 F v = W Tsinθ = N F hinge = F n +F v = 1000 N Q1. Fur particles, each with mass m, are arranged symmetrically abut the rigin n the x axis, as shwn in Figure. A fifth particle, with mass M, is n the y axis. The directin f the gravitatinal frce n M is: Figure A) Alng the negative y axis B) Alng the psitive y axis C) Alng the negative x axis D) Alng the psitive x axis E) Alng the negative z axis Hrizntal frces n M cancel ut due t symmetry while vertical cmpnents are added in the y axis directin.

6 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 6 Q14. A unifrm slid sphere has a mass f kg and a radius f 1.0 m. Find the magnitude f the gravitatinal frce due t the sphere n a particle f mass m = 1.0 kg lcated at a distance f 0.75 m frm the center f the sphere. F = GMm r A) N -7 B) N -7 C).6 10 N -7 D) N E) 0 = GM r r R M = N m = ρv = M 4 πr 4π r = r R M Q15. A planet has a mass f abut times the mass f Earth and a diameter f abut 0.81 times the diameter f Earth. The acceleratin f a bdy falling near the surface f this planet is: (take acceleratin due t gravity n earth t be 9.8 m/s ) A).77 m/s B) 1.50 m/s C) 5.95 m/s D) 9.80 m/s E).4 m/s g E = GM R g p g E = g p = GM P R P GM E R E = M P R E M E R P =.77 m/s (0.81) Q16. Neglecting air resistance, a 1.0 kg prjectile has an escape speed f abut 11 km/s at the surface f Earth. Find the crrespnding escape speed fr a.0 kg prjectile. A) 11 km/s B) 7. km/s C) 15 km/s D) 5.5 km/s E) km/s Escape speed is mass independent.

7 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 7 Q17. Tw satellites A and B f same mass f 10 kg are shwn in Figure, and mve in the same circular rbit f radius r = m arund earth but f ppsite senses f rtatin and therefre they are expected t cllide. If the cllisin is cmpletely inelastic, find the ttal mechanical energy immediately after cllisin. m 1 = m A) J 10 B) J 8 C) J 10 D) J E) 0 Figure v = v = v cm = 0 S after cllisin, KE = 0 E = N = GmM r = = J Q18. At a fixed depth within a fluid at rest, the pressure pushing upward is: A) Equal t pressure pushing dwnward. B) Zer, because pressure nly pushes equal in all hrizntal directin. C) Zer, because the fluid abve des nt supprt the weight f the fluid belw. D) Greater than the pressure pushing dwnward. E) Less than the pressure pushing dwnward. Cnditin fr fluid at rest.

8 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 8 Q19. A 5.0 kg rck whse density is 4800 kg/m is suspended by a string such that half f the rck s vlume is under water (see Figure 4). Find the tensin in the string. T = W B A) 44 N B) 7 N C) N D) 68 N E) 1 N T W B Figure 4 = ρ 0 v g ρ W v g = 1 ρ W ρ 0 mg = (5)(9.8) = 44 N 9600 Q0. Figure 5 shws vlume flw rates (in cm /s) f a fluid frm all but ne tube. Assuming steady flw f the fluid, find the vlume flw rate thrugh the X tube and its directin. Figure 5 A) 1 cm /s flwing ut B) 7 cm /s flwing in C) 5 cm /s flwing ut D) cm /s flwing in E) 4 cm /s flwing ut in +ve ut ve net lw rate = X = 0 X = 1

9 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 9 Q1. A 4.0 mm diameter hle is 1.0 m belw the surface f a large tank f water as shwn in Figure 6. Find water vlume flw rate thrugh the hle. A) m /s B) m /s C) m /s D) m /s E) m /s Figure 6 1 ρv = ρg (Y 1 Y ) v = g (Y 1 Y ) = 4.4 m/s R v = A v = πr v = m /s Q. Q. Fr an bject underging a simple harmnic mtin. Only ne statement is crrect A) The bject has varying acceleratin. B) The bject has varying amplitude. C) The bject has varying perid. D) The bject has varying frequency. E) The bject has varying ttal mechanical energy. In SHM acceleratin it is time dependent As shwn in Figure 7, tw identical springs f spring cnstant N/m are attached t a blck that is sitting n a frictinless flr. If the frequency f scillatin is 0.0 Hz, find the mass f the blck. Figure 7 A) 0.94 kg B) 0.16 kg C) 0.8 kg D) 0.00 kg E) kg f = w π = 1 π k m m = k f = 0.94 kg 4π

10 Phys101 Final Cde: 1 Term: 1 Wednesday, May 1, 014 Page: 10 Q4. A.000 kg blck, attached t a spring, executes simple harmnic mtin. The psitin f the blck is given as: x =.000cs(50.00t) where x is in meters and t is in secnds. Find the spring cnstant f the spring: k = mw A) 7500 N/m B) 6800 N/m C) 9000 N/m D) 560 N/m E) 4700 N/m = ()(50) = 7500 N/m Q5. A 50 kg by stands n frictinless level ice flr. He kicks a 0.10 kg stne lying near his feet if the velcity f the stne is (1.1 m/s)î, find the velcity f the by just after kicking the stne. A) ( m/s) î B) ( m/s) î C) ( m/s) î D) ( m/s) î E) 0 P befre = P after 0 = v fs m s + v b m b = (1.1 ı )(0.1) + v b (50) v by = (. 10 m/s) ı