PART I: MULTIPLE CHOICE (60 POINTS) A m/s B m/s C m/s D m/s E. The car doesn t make it to the top.

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1 Uit II Test (practice test for fall ) (Ch. 6 8, 0) Name: Physics Notes: the actual test will hae 0 m/c ad - writte problems. Also the test will coer ch. 9 (static equilibrium), which was ot coered o this old test. PART I: MULTIPLE CHOICE (60 POINTS). A roller coaster car starts from rest at a height of 00 m, coasts dowhill to groud leel the fially through a loop of radius 0m as show below. Igorig frictio, how fast is the coaster moig as it passes through the top of the loop? A. 4. m/s B. 5.4 m/s C. 5. m/s D. 6.6 m/s E. The car does t make it to the top.. What is the ormal force felt by a 80kg passeger as they pass through the top of the loop? A. 960N B. 8090N C. 6540N D. 80N E. The car does t make it to the top.. A geosychroous satellite completes oe orbit aroud the Earth eery 4 hr, so it ca stay aboe the same spot o the 4 equator. Gie that the mass of the Earth is kg, what is the orbital radius of a geosychroous satellite? A.. 0 m B..0 0 m C.. 0 m D..9 0 m E m 4. Two boxes are pulled alog a frictioless surface as show below. The boxes are pulled for 0 m. How much work is doe by T? 50kg T T 00N 00kg A. 400 J B J C J D. 000 J E. 000 J 5. or the situatio i Problem 4, how much work is doe by T o the 00 kg mass? A J B J C J D J E J

2 6. A ball of mass m=5 kg is dropped from a height of m aboe the ed of a large sprig, as show below. The sprig compresses by m before brigig the ball to rest. m m What is the sprig costat? A. 6 N/m B. 88 N/m C. 588 N/m D. 44 N/m E. N/m. or the situatio i Problem 6, the force exerted by the sprig (just as the ball comes to rest) is A. Larger tha mg. B. Smaller tha mg. C. Equal to mg. D. Zero E. More iformatio eeded. 8. A block of mass kg is slidig dow a ramp at a costat speed of 5 m/s. The iitial height of the block is m ad the coefficiet of kietic frictio is mu_k=0.. How much work is doe by frictio as the block slides all the way to the bottom of the ramp? m 5 m/s A J B. -5 J C J D. -44 J E. More iformatio eeded. =0 m 5m m 5m Problem 9 A explosio iolig uequal masses. 9. or the explosio show aboe, how does compare to? A. B. C. D A hollow sphere of mass M ad radius R rolls without slippig at speed. What percet of the kietic eergy is i the rotatio of the sphere? A. 40% B. 50% C. 5% D. 60% E. 8%

3 . A heay disk of mass kg ad radius 0 cm is placed o a support plate/hub assembly (like the lab we did). meter of strig is wrapped aroud the base of the hub (radius. cm), ad a costat tesio of 0 N is applied to the strig ad used to rotate the assembly from rest. or simplicity, you ca assume that the plate/hub assembly has egligible M.O.I. T=0N How fast will the whole assembly be rotatig after the strig is pulled all the way out? A..58 rad/s B. 5.8 rad/s C. 6.5 rad/s D. 0 rad/s E. rad/s. Two idetical objects are tied to strigs ad spu i circles with exactly the same agular elocity. Object A is tied to a shorter strig tha Object B. A B Which of the followig statemets are TRUE (fill i ALL aswers that apply)? A. The tesio i the strig is greater for object A. B. The speeds of both objects are the same. C. The period of rotatio is the same for both objects. D. The tesios i both strigs are the same. E. The tagetial acceleratios of both objects are the same.. A heay door for a bak ault is rectagular i shape ad higed at oe edge ( I 000 kg ad the width is m. A worker applies a force of 500 N to the edge of the door i order to fully ope it as show below. ML ). The mass of the door is 500N What is the agular acceleratio of the door (assumig there is o frictio)? A. 0.5 / rad s B. 0.5 / rad s C. 0.5 / rad s D..5 / rad s E..0 rad / s 4. How log does it take to ope the door (Problem ) all the way (90 degrees)? A..45 s B..05 s C..5 s D..89 s E. 5.5 s 5. A gridig wheel is made of a heay stoe disk of mass 8 kg ad radius 0 cm. It is attached to a 000W motor. If the wheel starts from rest ad the motor operates for 0.5 s, what is the fial speed of the wheel? A.. rad/s B. 5.8 rad/s C. 55 rad/s D. 9. rad/s E. 58 rad/s

4 Test (Ch. 6-8, 0) Name: PART II: WRITTEN CALCULATIONS (40 POINTS) It is critical that you show all your work/reasoig as clearly as possible o this part of the exam!. (0) A 0 kg cart is iitially moig at 5 m/s whe it is ru ito from behid by a 0 kg cart. The collisio is perfectly elastic ad takes place o a frictioless leel track. 0 kg 0 kg 0kg 0kg _0=? _0=5m/s _f=? _f=0 INITIAL STATE INAL STATE a. What is the perfect iitial elocity for the 0 kg cart, so it comes to a complete stop durig the collisio? b. What is the elocity of the 0 kg. cart after this collisio?

5 . (0) A gram bug starts from the ceter of a rotatig disk ad walks toward the outside edge. The disk is rotatig at a costat rotatio per secod (a motor is required to keep it at this costat alue). The coefficiet of static frictio is 0.9 betwee the bug s feet ad the disk. Agular elocity: rotatio/s (costat). a. How far from the ceter ca the bug walk before it breaks loose? b. How much kietic eergy is gaied by the bug as it walks outward from the ceter to the poit where it slips?

6 PHYSICS ORMULAS Uit I (Ch. -4): x t g 9.8 m/ s et ma 0 a 0 at x x0 0t at 0 a x x0 t b b 4ac 0 si V 0 y x R V Vx Vy ta Vx Vcos Vy Vsi a g V fkietic k N Uit II (Ch. 5-9): fstatic s N x r mm acetripetal cetripetal m f G G G Nm / kg T R r r T T r 60 W d cos KE m W W KE PEgra mgy PEsprig kx WNC KE PE E E costat P p m t p mx... mx pi pf maa mbb maa ' mbb ' xcm s r r a r t m... m acetripetal Irod r 0 t I Isolid sphere MR 5 ML (about oe ed) 0 Uit III (Ch. 0-): M V kx P A f T 0 0 0t t 0 0 r si Ihollow sphere MR Isolid disk Isolid cylider MR Irig Ipoit mass MR L ML (about the ceter) KErot I L I x 0 t y 0 Irod sg P gh P g h A A T f HO PE kx L x Acost f T g x A max L,,,... f,,,,... f L 4L,,,,..., f PV NkT mol Etot g f L f P gy P gy ka T ( db) 0log I, I0 T m k f T I m/ L r I0 0 /,,,,... sd obs f ' f u L sd source KE kt L L0 T T 9 T C 5 Additioal ormulas (Ch. 4): U NkT (coutig atoms istead of moles of atoms), Q mc T, Q ml, 4.86 J = cal k m W m, soud 0.6 T( C) kg k.8 0 / J K

04 - LAWS OF MOTION Page 1 ( Answers at the end of all questions )

04 - LAWS OF MOTION Page 1 ( Answers at the end of all questions ) 04 - LAWS OF MOTION Page ) A smooth block is released at rest o a 45 iclie ad the slides a distace d. The time take to slide is times as much to slide o rough iclie tha o a smooth iclie. The coefficiet