NYA final exam - Dec 2004 (with answers)

NYA final exam - Dec 2004 (with answers) - Dawson College...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 10
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Dawson College PHYSICS NYA FINAL EXAM1NATION Thursday December 16, 2004 Solve (a) any 8 of the 10 problems in part I (10 marks each) and (b) any 10 of the 14 conceptual questions in part ll (2 marks each). Formulae and constants are given at the end of this exam. You may detach the formula page. INSTRUCTIONS 1. The time allotted for this examination is three hours. 2. If you decide not to solve a particular problem, say problem 3, write: "Problem 3 — not worked". ' 3. Show all your work. 4. If you use more than one booklet, write the total number of exam booklets handed in on the top of the first booklet. Insert the additional booklets into the first booklet. 5. Write your name and the name of your teacher on the title page of each booklet. Good luck! 65) NYA - Final Exam Final Draft ~ Fall 2004.DOC Page I of 8 PARTI: Long Answer Questions Solve any EIGHT of the ten problems in part I 1. A rocket with total mass of 200 kg is fired upward from the ground with an initial acceleration of 20 rnfs2 for 30 seconds before running out of fuel. Neglecting air resistance, find: (a) the maximum height the rocket reaches. (b) Draw a velocity-time graph for the entire motion, and on the graph, label i) the maximum velocity and, ii) the time when the rocket reaches its maximum height. 2. For the three force vectors given find, (a) The x and y components for each vector, (b) the angle between 13:; and F2, (0) the magnitude and direction of the vector given by: m I III II align}: namm llllllllllllll jinn-Inuignnm 3. Little Johnny slides down a grassy 20° slope. When at the top of the slope, he was pushed such that he had an initial velocity. Johnny slides 3.50 111 down the slope before stopping. The coefficient of kinetic fiiction between grass and the seat of Johnny’s pants is 0.50. (a) Draw afiee~body diagram of Johnny as he is sliding down the slope. (b) What was Johnny’s initial Speed on the grass? 4. A ball is thrown with a velocity of 30.0 111/5 at an angle l ‘ of 15.0° below the horizontal as shown in the figure. I 15° The ball hits the ground 5.00 seconds after being i . _‘Vo.“3° InIE released. Find i _ l N. ~_ K (a) the height h from which it is thrown, h i \ \ (b) the horizontal distance travelled (R), and ‘ t X (c) the magnitude and direction of the velocity with ' . which it hits the ground. Q"— R —"———"'"'—"'> (L? Page 2 of 8 5. A car driving along a road at a constant speed of 25.0 mls is shown at three different positions as it is moving along a flat stretch of road (A), as it is at the bottom of a dip (B), and as it reaches the top of a hill (C). Ifthe radius of curvature for the dip and the hill are both 200 m (as shown) and the driver of the car has mass 70.0 kg, answer the following: (a) What is the driver’s apparent weight at points A, B and C? (b) What is the mmimum speed the car could haVe at point C and remain in contact with the road? (c) Ifthe driVer were to apply the brakes as hard as possible at each of the points A, B and C, where would the car decelerate the most? Justify your answer. 6. A 2.00 kg block is placed on top of a 5.00 kg block as shown. The coefficient of kinetic friction between the 5.00 kg block and the surface is 0.200. Friction is also present between the upper and lower blocks. A horizontal force F is applied to the 5 .00 kg block. (a) Draw a flee-body diagram for each block. (b) What force is responsible for causing the acceleration of the 2.00 kg block? (c) Calculate the magnitude of the force necessary to pull both blocks to the right with an acceleration of 3.00 m/sz. (d) Find the minimum coefiicient of fi'iction between the blocks such that the 2.00 kg block does not slip with an acceleration of 3.00 m/sz. 7. Two blocks composed of the same material are in contact on a rough table. A horizontal force F is applied to one block, as shown. If m = 2.00 kg, m; = 1.00 kg, and F= 16.0 N, and the coefficient of kinetic friction between the table and the blocks is 0.150, (a) draw flee-body diagrams for m and m;. (b) Find the numerical values for the normal forces of the table on m1 and m2. (c) What is the acceleration of the blocks? ((1) Determine the force of contact between the two blocks. 2:8 Page 3 of 8 8. A 2.00 kg object is moving to the right with a speed of 1.00 m/s when it experiences an impulse due to the force 11;: (N) shown in the graph. 5 . (a) What is the object’s speed after the impulse? 0 t (5) (b) What is the object’s direction after the impulse? 0 2 4 6 9. A block of mass m is released from rest and slides down a fi-ictionless track, as shown. It then hits a stationary block of mass 3m. (a) Suppose the two blocks stick together. How fast are 1/ In they moving just after the collision? (b) Suppose the collision is perfectly elastic. To what height does the block of mass m rebound after the collision? 10.An 8.00 kg block is sliding horizontally to the right at 5.0011113, at the instant it shikes a relaxed spring of k= 500 N/m. The coefficient of kinetic friction between table and block is pk = 0.300. ' TAgLE (3.) Draw a fi'ee—body diagram for the block as it is compressing the spring. (b) Use the work-kinetic energy theorem to find the maximum distance, x, that the spring is compressed fiorn its original (relaxed) length. END ofPARTI “Q! 20‘ Page 4 of 8 PART II: Conceptual Questions Answer any TEN of the fourteen conceptual questions in part II ANSWER ALL QUESTIONS IN THE ANSWER BOOKLET - . A stone is thrown vertically upwards, reaches a highest point, and returns to the ground. When the stone is at the top of its path, its acceleration is (a) directed downwards. (b) changes direction from upwards to downwards. (c) is zero. ((1) is directed upwards. . All objects moving in acircle are accelerated, TRUE or FALSE. (a) The components of a vector will be the same no matter what coordinate system is used to express that vector, TRUE or FALSE. (b) The maggitude of a vector remains the same in a difl‘erent coordinate system, TRUE or FALSE. . Reproduce the following diagram in your answer booklet. (a) Identify the direction of the acceleration vector 22' and show it on the diagram. (b) Identify the direction of the velocity vector 17 on the diagram and justify your choice. (c) Write a short description of a real object for which this is the correct free-body diagram. . A person gives a shopping trolley an initial push along a horizontal floor to get it moving, then lets go. The trolley travels forward along the floor, gradually slowing as it moves. Consider the horizontal force(s) on the trolley while it is moving forward and slowing. Which of the following is correct? (a) Both a forward and a backward force are acting on the trolley, but the forward force is larger. (b) Only a forward force is acting which diminishes with time. (c) Both a forward and a backward force are acting on the trolley, but the backward force is larger. ((1) Only a backward force is acting, no forward force. Pa e50f8 ’50 g (a) As a projectile moves on its parabolic path, is there any point along the path where the velocity and acceleration vectors are: i) ' perpendicular to each other? Ifso, state where in the motion this occurs. ii) parallel to each other? If so state where in the motion this occurs. (b) A rock is dropped at the same instant that a ball, at the same elevation, is thrown horizontally. Which will have the greater speed when it reaches ground level? 7. A particle moves clock-wise around a circle at constant speed for 2.05. It then reverses direction and moves counter-clock-wise at halfthe original speed until it has travelled through the same angle. Which is the particles angle versus time graph? 9 9 fl 9 R74 !' Wt %: t g t (I!) (h) (c) (d) 8. A ball on a string is swung in a vertical circle. The string happens to break when it is parallel to the ground and the ball is moving up. Which trajectory does the ball follow afler the string breaks? 9. A large truck collides head-on with a cyclist. During the collision (a) the truck exerts a force on the cyclist, but the cyclist exerts no force onto the truck. (b) the truck exerts the same amount of force on the cyclist as thecyclist exerts on the truck. (c) the truck exerts a smaller amount of force on the cyclist than the cyclist exerts on the truck. (d) the truck exerts a greater amount of force on the cyclist than the cyclist exerts on the truck. 3‘ Page 6 of8 10. Two fiiends are standing on opposite ends of a canoe. The canoe is initially at rest with respect to the lake. The person on the right throws a very maSSive ball to the left, and the person on the left catches it. After the ball is caught, the canoe is (ignore fiiction between the canoe and the water) (a) moving to the left, (b) stationary. (c) moving to the right. 11. A ball can be rolled dowu one of four different ramps, as shown below. The final elevation loss of each of the ramps is the same. Neglecting friction, for which ramp will the speed of the ball be the highest at the bottom? (a) The speed of the ball will be the same for all ramps. (b) Ramp Y (c) Ramp Z (d) Ramp X 12. Two cars collide, lock bumpers and eventually slide to a stop due to fi'iction with the roadway. During this entire process, mechanical energy and momentum are both conserved. TRUE or FALSE. 13. A rubber ball dropped fiom a height h above the ground. Describe the motion of the ball for many bounces if the collision is completely elastic. 14. A grandfather clock swings back and forth. Does the force of gravity do positive work on the pendulum at any point in its trajectory? If so, where? END of EXAM “Q! . Page 7 of 8 3L Pbb-ISIES Deer I: U a) Mu: Maw mm 4-,, 27.4%“ v“ .q—nmu:«9111::qu1 5) WA 5) ’12; wig em E, We E: I; '1er J (L3 '7 3’“ (it 61.55 [1051M y—axid 3> as a 7‘ :1 ‘5 74+ LJLM e = 203 9 A. U '33 V' : 3.0Ml5 l 43 a) 7h Mu WC» mm Maw 72% W mm 10) m urrfiauw Mm mm W n= 14m a) 7L!— Mfijfll‘w 4‘4 62'49‘4/1 a} 62.30 é’efiam magmas. I 5' a AMM'M d #13 men) 6,96%»,- 4051) B 3 (9:3 J OZ {Vi 4G7” ,_ -' 53 TL mkfmm SM afi‘ C 4L4 W-3w/S a) 3m m rm. 7 1429mm dam Maj“; abs—n9- Slm 5"“‘4 (“OW-kg 11¢ mmfiw /?3/ kmltiufi occurs LJLm nrs mu: .3. my! piece}. air 6_ e) ab zlzjumccfia', ‘ 51(54Zook:_, [j]? 4? f w w, 1 a it) 72-H— wv—bu 4mg. ameflmmfe—a 72L 2!! (174191.. 'fiAmmL 6A mfltzkj W95 -C’) F“; 351) 44 [121.4251 jlu 6:354/32'. ‘36 71-“ MIN-“WM “7/de 5} Wm 13’ /uS: 0.3! :11“ CL 1M : " é _ 3 B 1 F “I I My 7‘: I a mi: E- J kl 'F A .3, “.1 u; f '05 Vii : aqu {A}: _ a) m dam a; Tie. black; (‘5 0.5—0'1‘u/sL—eb 0\) rile. A) Cod-ad: F”. : F2]: liq?“ _ ‘23 CO 77—2 JhAlauflM. VX = Hun/g- ' fifier 71.2. daft-LA 71a ALJMJG {'5 9M? No.43 {a FILL [dos‘nlire K‘chr" ' 5T3 C's Colluéul.‘ 72-9. M0904: LI-wvt afl' 2.2144/5 Q Hater cam ’14”; M Idlime # a. haw-7 Lo“ 10) a} é LE, _ fl __ ’ I» 72.». my. charm X Aid 0.587»: W? P MA I It sis par-II: 040‘0'1‘ emu ausm-n. (Coding-9:) I) a 25m 33 a) False. In) “hum. .5) am ()5 0.3 (1) Vauél a: a) a ‘ 1' Jim 'SCLW-L \ gig-$3“ CM fie? Q A . V UBLXSJL‘ J14 dosrfe, \ Kiwi-It. Em; a.) 1m latmk migwr 5e Sufi U10 ICL muclk I'uc'\u_n__' afie- b as 31143 I 30. 631’ 719. £73 ffofillnolsi. [flaflx are I ’— 56 \7 mg. a dirt Maver- paraffefl 53 (IL; Rad: 7km LLoU'JOBLELEQ] L44 firmkr I1) ELISE. :3) m w #wfi loqu M in «3,44% 1min; 14B YES, remit] 4419.5 [dosifix're wank Cid/L. Pwflu mu Gui-Q?! down. fl W ...
View Full Document

Page1 / 10

NYA final exam - Dec 2004 (with answers) - Dawson College...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online