phy136h-d11 copy 2.pdf

• NAME (PRINT): LasUSurname First IGiven Name STUDENT#: _ __ _ _ ___ _ _ SIGNATURE: _ _ __ ___ _ UNIVERSITY OF TORONTO MISSISSAUGA DECEMBER 2011 FINAL EXAMINATION PHY136H5F Introductory Physics I Wagih Ghobriel Duration - 3 hours Aids: Calculator Model(s): Any calculator programmabre or not. The University of Toronto Mississauga and you, as a student, share a commitment to academic integrity.You are reminded that you may be charged with an academic offence for possessing any unauthorized aids during the writing of an exam, including but not limited to any electronic devices with storage, suchcell phones, pagers, personal digital assistants (PDAs), iPods, and MP3 players. Unauthorized calculators and notes are also not permitted. Do not have any these items in your possession in the area of your desk. Please tum the electronics off and put al/ unauthorized aids with your belongings at the front of the room before the examination begins. Iany of these items are kept with you during the writing of your exam, you may be charged with an academic offence. A typical penalty may cause you to fail the course. Please note, you CANNOT petition to re-write an examination once the exam has begun. Notes to students o The exam consists of twenty (20) equally-valued multiple-choice problems. o The total number of pages is 21, including the front page. o Total mark equals 100. o The formula sheet will be handed out separately and must be handed in with the question sheets at the end of the exam. o Choose only one answer in each problem. o Please fill in the scantron sheet very carefully including your name and ID number. The scantron sheet will be the only paper that will be marked. Your answers on the problem book will not be marked. You can use the available extra blank space in this book as a draft. o You are not allowed to bring your own prepared sheet of formulas or any other source of information. You'll be provided with all the constants and formulas that you may need in this exam. continued on next page 2 PHY136HSF Dec 2011 Final Regular Exam page 2 of 21 [5] (1) A 225-kg crate rests on a sUlface that is inclined above the horizontal at an angle p of {} = 20.0°. A horizontal force P (magnitude = 535 N and parallel to the ground, not 4--", the incline) is required to start the crate moving down the incline . What is the coefficient of static friction between the crate and the incline? {...._____ ..... (a) 0.712 (b) 0.665 (c) 0.538 (d) 0.473 (e) 0.326 continued on next page 3 PHY136H5F Dec 2011 Final Regular Exam page 3 of 21 [5] (2) Block A in the figure weighs 2.N, and block B weighs 5.40 N. The coefficient of kinetic friction F between all surfaces is 0.25. Find the magnitude of .----t.:.:.: ..:l.:.:.:.1------: ........ the horizontal forceF necessary to drag block B to by a light cord passing around a fixed, frictionless pulley. (a) 8.45 N (b) 7.53 N (c) 6.21 N (d) 5.74 N (e) 3.38 N continued on next page 4 PHY136H5F Dec 2011 Final Regular Exam page 4 of 21 [5] (3) A 30.0-kg block is resting on a flat horizontal table. On top of this block is resting a 15.0-kg block, to which a horizontal spring is attached, as the drawing illustrates. The spring constant of the spring is 325 N/m. The coefficient of kinetic fiction between the lower block and the table is 0.600, and the coefficient of static !iction between the two blocks is 0.900. A horizontal force is applied to the lower block as shown. TIlls force is increasing in such a way as to 30.0 kg F keep the blocks moving at a constant speed. At the point where the upper block begins to slip on the lower block, determine (i) the amount by which the spring is compressed and (ii) the magnitude of the forcF. (a) (OA07m, 397 N) (b) (OA10m, 597 N) (c) (OA10 m, 179 N) (d) (0.230 m,198 N) (e) (0.058 m, 397 N) continued on next page 5 PHY] 36H5F Dec 2011 Final Regular Exam page 5 of 21 [5] (4) A "swing" ride at a camival consists of chairs that are swung in a circle by 17.0-m cables attached to a vertical rotating pole, as the drawing shows. Suppose the total mass of a chair and its occupant is 90.0 kg. Determine the tension in the cable attached to the chair when its velocity is 38.0 m/s. [Hint: You may need to solve a quadratic equation to find e .J ▯▯▯▯▯▯▯▯▯▯▯▯▯▯ ▯▯ ▯ ▯▯ (a) 9361 N (b) 8934 N (c) 7745 N --- R ---- _ (d) 5175N (e) 3082 N ---------------- continued on next page 6 PHY136H5F Dec 2011 Final Regular Exam page 6of 21 [5](5) A small ball is attached to one end of a spring that has an unstrained length of 0.200 m. , unstrained , The spring is held by the other end, and the ball is spring v = ▯▯▯▯▯▯mls whirled around in a horizontal circle at a speed of 1+ 0.200 m -.j 3.00 mls. The spring remains nearly parallel to the ground during the motion and is observed to ▯▯ stretch by 0.010 m. By how much would the same I spring stretch if it were attached to the ceiling and I III the ball allowed to hang straight down, 1 2 ,, 3 motionless? (a) 6.08 mm (b) 5.47 rom (c) 4.93 rom (d) 2.29 mm (e) 1.15 nun continuedallnext page 7 PHY136H5F Dec 2011 Final Regular Exam page 7 of 21 [5] (6) Two particles are located xaxis. Particle 1 has a maand is at the origin. Particle 2 has a mass 2m and is ax= +L.A third particle is placed o+xtaxis between particles 1 and 2. Where xnaxis should the third particle be located soe magnitude of the gravitational force on both particle 1 and particle 2 doubles? (i.e. Find the valueExpress your answer in terms of L. (a) 0.414 L (b) 0.573 L (c) 0.612 L (d) 0.705 L (e) 0.885 L L D I: ▯▯▯ +x •m • 2m continued on next page 8 PHY136H5F Dec 2011 Final Regular Exam page 8 of 21 [5](7) A 3.0 kg block is dropped from a height of 80 cm onto a spring of spring constant k = 1960 N/m, as shown in figure. Find the maximum distance the spring is compressed. o (a) 0.07 m (b) 0.ill (c)0.17m (d) 0.ill (e) 0.25 m T h= 80.0 cm ! ▯▯ k= 1960 N/m continued on next page 9 PHY136H5F Dec 2011 Final Regular Exam .,page 9 of 21 [5](8) of weight = 588 N falls the ground. During the the ground, he comes to rest of 0.01 s. The average by the ground is +20000 N, upward direction is taken to be From what height did"....."fall? Assume that the only T the collisionthat h (a) m (b) 0.79m (c) m (d) m (e) 0.42 m continued on next page 10 PHY136H5F Dec 2011 Final Regular Exam page 10 of 21 [5](9) A 10 gram bullet is fired horizontally into a 2.50-kg wooden block attached to one end of a massless, horizontal spring (k= 845 N/m). The other end of the spring is fixed in place, and the spring is unstrained initially. The block rests on a horizontal, frictionless surface. The bullet strikes the block perpendicularly and quickly comes to a halt within it. As a result of this completely inelastic collision, the spring is compressed along its axis and causes the blocklbullet to oscillate with amplitude of 0.200 illWhat is the speed of the bullet v?