Final Exam Cheat Sheet and Questions | General Physics I | PHYS 121, Exams of Physics

Download Final Exam Cheat Sheet and Questions | General Physics I | PHYS 121 and more Exams Physics in PDF only on Docsity! P. 1 / 4 /home/richard/aainfors/Tech/Phys121_Spring07/Quizzes/final2.doc YOUR NAME – _____________________________________ PHYSICS 121 – FINAL EXAM Useful constants: 8 2 45.67 10 W m K   , 116.67 10G  319.1 10ELECTRONm kg  181 6.0 10 ( )Joule electon Volts eV  30.9OLIVE OIL g cm   210.0 ( ) m g for convenience s  Conceptual or short answer questions [4 points each – You are not required to explain your answers, but you may if you want to justify the answer or explain an assumption you made in choosing that answer.] 1) What are the proper SI units for: a) the Gravitational constant “G”, b) for momentum, c) angular momentum, d) torque ? [There is more than one correct answer to each of the parts of this question – you only need to provide one.] 2) Write down the formulae for: a) Circumference of a circle b) Area of a circle c) Surface area of a sphere d) Volume of a sphere 3) A steel ball of volume 33 m is immersed in pure olive oil. (Density is listed above). What is the buoyant force on the ball (in Newtons)? 4) A woman exerts a constant horizontal force on a large box. As a result, the box moves across a horizontal floor at a constant speed. The constant horizontal force applied by the woman: (A) has the same magnitude as the weight of the box. (B) is greater than the weight of the box. (C) has the same magnitude as the total force which resists the motion of the box. (D) is greater than the total force which resists the motion of the box. (E) is greater than either the weight of the box or the total force which resists its motion. 5) If the woman in the previous question doubles the constant horizontal force that she exerts on the box to push it on the same horizontal floor, the box then moves: (A) with a constant speed that is double the speed in the previous question. (B) with a constant speed that is greater than the speed in the previous question, but not necessarily twice as great. (C) for a while with a speed that is constant and greater than the speed in the previous question, then with a speed that increases thereafter. P. 2 / 4 /home/richard/aainfors/Tech/Phys121_Spring07/Quizzes/final2.doc (D) for a while with an increasing speed, then with a constant speed thereafter (E) with a continuously increasing speed. 6) Two metal balls of different masses are held 2 meters above level ground and released as follows: The first ball is released from rest and falls straight down. The second ball is given an initial horizontal velocity of 9.8 m/s, and released at the same instant as the first ball. (A) The more massive ball hits the ground first. (B) Both balls hit the ground at the same time. (C) The ball with zero horizontal velocity hits the ground first. (D) The ball with initial horizontal velocity of 9.8 m/s hits the ground first. (E) More information is needed. 7) You are throwing a ball straight up in the air. At the highest point, the ball’s (A) velocity and acceleration are zero. (B) velocity is nonzero but its acceleration is zero. (C) acceleration is nonzero, but its velocity is zero. (D) velocity and acceleration are both nonzero. Long Answer Questions [12 points each] [Show your work on separate pages – particularly if you wish to receive partial credit – a correct answer with no supporting equations/calculations will not be accepted.] 8) A rope is stretched between supports 12 m apart; its tension is 52 N. If one end of the rope is tweaked, the resulting disturbance reaches the other end 0.45 s later. a) What is the total mass of the rope? b) Sketch the appearance of the standing waves in the rope with the three lowest frequencies. c) What are the frequencies and wavelengths of the three lowest frequency standing waves in this rope? 9) A 200 g mass is attached to a spring of constant 7.0 /k N m and cm set into oscillations with A=25 cm. [Ignore the effect of gravity when solving this problem] Determine: a) The frequency of oscillations (in Hertz) b) The period of these oscillations. c) The maximum velocity of the mass. d) The maximum force on the mass. e) The maximum and minimum energy stored in the spring over one cycle of oscillations. 10) We showed in class that the solar constant for Earth, (the amount of power reaching one square meter of Earth’s upper atmosphere on the equator) is 21400 W S m  . For Mars, the solar intensity is only 2600 W S m : . a) How far is Mars from the sun? (The Earth is 111.5 10ESR m from the sun.) [You don’t need this answer to do part b – nor do you need part b to answer this!]