= m. Suppose the speed of a wave on a string is given by v = Κ τμ

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1 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 1 Q1. Find the mass f a slid cylinder f cpper with a radius f 5.00 cm and a height f 10.0 inches if the density f cpper is 8.90 g/cm 3 (1 inch is equivalent t.54 cm). ) 17.8 kg B) 10.5 kg C) 5.43 kg D) kg E) 13.3 kg r = 5.00 cm = 5 10 m h = (10.0 in).54 cm 1 m = 0.54 m in 100 cm ρ = 8.90 g cm 3 cm 10 1 m 3 1 kg 10 3 g = kg/m 3 m = ρ πr h = ( ) 7 ( ) (0.54) = = 17.8 kg Q. Suppse the speed f a wave n a string is given by v = Κ τμ m n, where K is a dimensinless cnstant, τ is the tensin in the string, and µ is the mass per unit length f the string. Find the values f m and n. ) m = +1/, n = 1/ B) m = +1/, n = +1/ C) m = 1/, n = 1/ D) m = +3/, n = 3/ E) m = +1/, n = 3/ [v] = [τ m ][µ n ] LT 1 = (MLT ) m (ML 1 ) n LT 1 = M m L m T m M n L n = M m+n L m n T m m = 1 m = 1 m + n = 0 n = m = 1

2 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: Q3. car driver maintains a speed f 0 km/hr fr the first half f the distance t his destinatin. In rder t have an average speed f 30 km/hr fr the entire trip he has t maintain fr the last half f the trip a speed f: ) 60 km/hr B) 40 km/hr C) 50 km/hr D) 45 km/hr E) 35 km/hr L B L C v avg ttal = 30 = v v v = 1 15 L t ttal = L t B +L BC = v = L L 0 + L vavg 15 v = 0 v 5v = 300 v = 60 km/hr Q4. Sitting n the tp f a building, yu drp (release) a stne while yu thrw a secnd stne dwnward. Which curves in Figure 1 give the velcity v(t) fr the drpped stne and the thrwn stne, respectively? ) Curves and B. B) Curves and C. C) Curves B and D. D) Curves C and B. E) Curves D and C. Figure 1

3 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 3 Q5. The velcity f a truck mving in a straight line is given by ( ) 3 vt = t t.0 twhere v is in m/s and t is in secnds. Find the velcity f the truck at the instant when its acceleratin is 6.0 m/s. ) 0 B) +8.0 m/s C) 8.0 m/s D) +4.0 m/s E) 4.0 m/s v (t) = t 3 t t a (t) = 3t t = 6 3t t 8 = 0 t = + ± v() = = 0 = ± ; t = s Q6. n bject is in a unifrm circular mtin in a hrizntal circle f radius 10.0 m. If it cmpletes.50 rtatins in 10.0 s, starting at pint (Figure ), find its average velcity. ).00 m/s tward Nrth B).00 m/s tward Suth C) 15.7 m/s tward East D) 15.7 m/s tward West E) 8.86 m/s tward West Figure D = C = 0 m Nrth v = 0/10 =.00 m/s Nrth

4 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 4 Q7. Q8. Which f the fllwing is a vectr that is perpendicular t vectr ( 3iˆ kˆ ) ) ( iˆ+ ˆj 3kˆ ) B) ( iˆ+ ˆj) C) ( ˆj 3kˆ ) D) ( iˆ + 3kˆ ) E) ( 3kˆ ) +? Vectr has a magnitude f 3.0 and makes an angle f 60 B with the psitive x-axis. Vectr has x and y cmpnents f.0 and +4.5, respectively. Find the angle between 3 B and B. the vectrs ( ) ) 90 B) 45 C) 66 D) 4 E) 0 vectr 3 B B θ = 90

5 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 5 Q9. n airplane starting frm airprt flies 500 km east, then 00 km 30 west f nrth, and then 17 km nrth t arrive at airprt B. The next day, anther plane flies directly frm t B in a straight line. In what directin shuld the pilt travel in this direct flight? Ignre the effects f air. Nrth = 500 ı ) 37 nrth f east B) 50 nrth f west C) nrtheast D) nrth E) nrthwest West 00 30ᵒ B 60ᵒ 17 C 500 East B = 00 cs 60 ı + 00 sin 60 ȷ Suth C = 17 ȷ R = + B + C = 400 ı ȷ θ x = cs = Q10. Car is mving with a speed f 10.0 m/s in a directin 30.0 nrth f east. Car B is mving with a speed f 10.0 m/s in a directin 30.0 nrth f west. Find the velcity f car relative t car B. Nrth ) 17.3 m/s due east B) 17.3 m/s due west C) 10.0 m/s due nrth D) 10.0 m/s due suth E) 13.7 m/s due nrth-west West CR B 30ᵒ 30ᵒ CR East v B = v v B = 10 cs 30 ı + 10 sin 30 ȷ + 10 cs 30 ı 10 sin 30 ȷ Suth = 0 cs 30 ı = 17.3m/s ı

6 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 6 Q11. Q1. Q13. Figure 3 shws three paths fr a sccer ball kicked frm grund level. Rank the paths accrding t the time f flight, greatest first. Ignre the effects f air. ) ll tie B) Path 1, Path, Path 3 C) Path 3, Path, Path 1 D) Path, Path 1, Path 3 E) Path, Path 3, Path 1 y In Figure 4 particle P is in a unifrm circular mtin, centered n the rigin f an xy crdinate system. t what values f θ is the y cmpnent f the particle s acceleratin greatest in magnitude? ) 90 and 70 B) 0 and 180 C) 0 and 90 D) 90 and 180 E) 0 and 70 particle is mved ver an xy plane with acceleratin cmpnents a x = 4.0 m/s and a y =.0 m/s. Its initial velcity has cmpnents v x = 8.0 m/s and v y = 1 m/s. What is the speed f the particle when it reaches its greatest y crdinate? ) 3 m/s B) 1 m/s C) 8.0 m/s D) 16 m/s E) 0 v fy = v 0y + a y t 1 Figure 3 y θ 3 Figure 4 P x x t = 1 = 6.0 s v fx = v 0x + a x t = = 3 m/s

7 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 7 Q14. persn measures the acceleratin f an bject and finds a value + 10 iˆ m/s. nther persn, mving at a cnstant velcity v = iˆ m/s with respect t the first ne, makes an acceleratin measurement n the same bject at the same time. The value f the acceleratin fund by the secnd bserver is ) + 10 iˆ m/s B) + 15 iˆ m/s C) iˆ m/s D) 10 iˆ m/s E) 5.0 iˆ m/s Q kg bject is accelerated upward by a crd f negligible mass. The maximum tensin that the crd can take befre breaking is 75.0 N. Find the maximum upward acceleratin that can be given t the bject. ) 5.83 m/s B) 9.81 m/s C).9 m/s D) 16.0 m/s E) 10.0 m/s T mg = ma a = T mg m = T m g = = = 9.8 = 5.83 m/s 4.8

8 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 8 Q16. n 800 N persn is standing n a scale inside an elevatr at rest. Suddenly the elevatr cable breaks and the elevatr is in free fall. The weight f the persn as indicated by the reading n the scale nw is: ) 0 N B) 800 N C) 1600 N D) 400 N E) 1000 N Q17. bk is resting n a hrizntal table. The reactin frce t the weight f the bk is ) The frce with which the bk is pulling n Earth B) The nrmal frce frm the table n the bk C) The supprt frce frm the flr n the table D) The frce with which the bk is pushing n the table E) The frce with which the table is pushing n the flr Q18. Frictin and nrmal frces are always ) Perpendicular t each ther B) Oppsite t each ther C) Equal t each ther D) In the same directin E) Nne f the thers

9 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 9 Q19. blck with mass m 1 is placed n an inclined plane with slpe angle α and is cnnected t a secnd hanging blck with mass m by a light crd passing ver a massless and frictinless pulley (Figure 5). The cefficients f static and kinetic frictin are µ s and µ k respectively. If the blcks are released frm rest, fr what range f values f m will they remain at rest? Figure 5. m 1 (sinα µ s cs α) < m < m 1 (sinα + µ s cs α) B. m 1 (sinα µ s cs α) < m < m 1 (sinα + µ k cs α) C. m 1 (sinα µ k cs α) < m < m 1 (sinα + µ s cs α) D. m 1 (sinα µ k cs α) < m < m 1 (sinα + µ k cs α) E. m 1 (csα µ s sin α) < m < m 1 (csα + µ s sin α)

10 Phys101 First Majr-11 Zer Versin Sunday, Octber 07, 01 Page: 10 Q0. What is the radial acceleratin f the mn due t its mtin arund the earth? ssume the mn is mving arund the earth in a circular rbit with a perid f 8 days. Take the distance f the mn t the center f the earth t be f 3.85 x 10 5 km. a = v r a = πr T r = 4π r T ).60 x 10 3 m/s B).60 x 10 6 m/s C) 4.13 x 10 4 m/s D) 4.13 x 10 7 m/s E) 6.8 x m/s T = s ; r = m = = , = = m/s