PHYS 101 Final, Fall 1995

AMMTCAN CNIVEDSIV LIBRARY OF LEIRUT Physics 101 Final Exam Feb 34, 1996 Time : 2 hours ID. No. . Encircle your section sect. 1. 11, MWF & 1, F sect. 2, 9,TT & 11, TT sect.3. 9,TT & 2-4 F Dr. Bodakian Dr. Zableet Dr. Katul Physics 101 Final Exam Feb. 3'd, 1996 Time : 2 hours Part A: I. The apparent weight of a 60-kg man in an elevator going up with an acceleration of 2.0 ns is in N : 77 a) $30 b) 590 c) 650 4) 710 ©) none of the above, my answer is: IL A body sliding down a 30° incline of 11, = 0.20, has a constant acceleration of a) 2g b) g c) 9/2 d) g/3 €) none of the above, my answer is : TV. A 0.15-kg ball ia moving at a speed of 40 m/s when itis struck by a bat that reverses its direction and gives it a speed of 60 m/s. What average force was exerted by the bat if it was in contact with the ball for 5.0 ms. a)1500N —_b) 600'N ©)2500N — d) 3000N a €) none of the above, my answer is : ees ¥. A soccer player kicks a ball at an angle of 37° above the horizontal with an initial peed of 15 m/s. Assuming that the ball reaches the highest point of its trajectory, at what time will it be reached 7 155s 0.928 193s 0.565 €) none of the above, my answer is : eee Physics 101 Final Exam Feb. 314, 1996 Time ; 2 hours VL 1) An automobile of mass 1360 kg has wheels 76.2 cm in diameter and of mass 27.2 kg cach. Taking into account the rotational kinetic energy of the wheels about their axles, what is the total kinetic energy of the automobile when traveling at 80 knv/h? a} 1.54x1033 by2.84x1043- 6)3.84 x105J = d) 2.841055 e) none of the above, my answer is : 2) Considering that each wheel has a mass distribution equivalent to that of a uniform dink, what percentage of the kinetic energy belongs to the rotational motion of the wheels about their axles ? a) 2.0% b) 2.7 % ©) 3.2% d) 3.9% e) 6.0% f) none of the above, my answer is : ’ VIL. The pulley of an Atwood machine is a brass disk of mass 120 g, Masses m = 450-g and mz = 455-g are suspended at the extremities of a massless string that runs without slipping over the pulley. It is found that the larger mass descends 1.6 m in 8.0 8 starting from rest. The value of g (gravity acceleration) under the conditions of the experiment is in m/s2. a) 8.7 4) 9.1 )95 9.7 e) 9.8 e) none of the above, my answer is : VIIL A 4.0 kg block extends a spring 16 cm from its unstretched position. The block is removed and a 0.5-kg body is hung from the same spring, If the spring is then stretched and released, the period of oscillation of the system is: a) 0.42.8 b) 0.155 ¢) 0.558 d) 0.28 8 : y e) none of the above, my answer is : 3 Physics 101 Final Exam Part B; 1. A physical pendulum has the shape of a disk of radius R. The pendulum swings about an axis perpendicular to the plane of the disk and at . distance L from the center of the disk. a) Show that the angular frequency of c the oscillations of this pendulum is (= yee, + b) For what value of L is this frequency at = a maximum ? Feb. 374, 1996 Time ; 2 hours ni Physics 101 Final Exam II. Consider the system shown by the adjacent figure. The table is frictionless and the pulley is light and frictionless. a) Find the acceleration of the system for m = 1.0-kg b) Find the tensions T; and F. c) Find the work done by T2 on 2m as m falls through 1.0 m. Feb. 3°4, 1996 Time : 2 hours \ S ” Physics 101 Final Exam Feb. 3'4, 1996 Time : 2 hours of ‘ ; UI. A chain mass m and length L is held chain 53 7 on a frictionless table with one fifth O00EE © of its length over the edge. Find the “Tab le work required to pull the hanging . part back on the table. Physics 101 Final Exam IV. Two skaters collide and embrace in a completely inelastic collision. That is they stick together after impact. One, whose mass my, is 70-kg, is initialty moving cast at 6.0 knvh while the other, whose mass m is 50-kg is initially moving north at 8.0 kiwh. Calculate : a) The final velocity of the couple. b) The initial kinetic energy of the skaters. ¢) The final kinetic energy of the skaters, d) The fraction of the initial kinetic energy of the skaters lost because of the collision. Physics 101 Final Exam Feb. 3'4 , 1996 V. A uniform disk rotates about a fixed axis, starting from rest and accelerating with a constant angular acceleration. At one time it is rotating at 10 rew/s. After completing 60 more complete revolutions its angular speed is 15 rev/s. Calculate : a) Its angular acceleration in rev/s? b) The time required to complete the 60 revolutions. c) The time required from the start to attain the 10 rev/s angular speed. Final Exam Feb. 3°d , 1996 Time : 2 hours ‘axis between the points x = 0.20 m is 1.2 5 and itis simple harmonic, = 0.0 m and its velocity is Positive. a) What is the frequency of the motion 7: b) What is the angular frequency ? c) What is the amplitude of the motion ? d) What is the phase constant ? ©) At what time will the particle reach the point x = 0.10 m for the firs time ? ) What is the speed of the particle when it is at x = 0.10 m?