Physics Honors Page 1

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1 1. An ideal standard of measurement should be. variable, but not accessible variable and accessible accessible, but not variable neither variable nor accessible 2. The approximate height of a 12-ounce can of root beer is m m m m 3. A bullet is fired horizontally from the roof of a building 100. meters tall with a speed of 850. m/s. Neglecting air resistance, how far will the bullet drop in 3.00 seconds? 29.4 m 44.1 m 100. m 2550 m 4. Two 10.0-newton forces act concurrently on a point at an angle of 180 o to each other. The magnitude of the resultant of the two forces is. 0 N 10.0 N 18.0 N 20.0 N Base your answers to questions 5 and 6 on the diagram below which represents a ball being kicked by a foot and rising at an angle of 30.º from the horizontal. The ball has an initial velocity of 5.0 meters per second. [Neglect friction.] 12. Starting from rest, object A falls freely for 2.0 seconds, and object B falls freely for 4.0 seconds. Compared with object A, object B falls one-half as far twice as far three times as far four times as far 13. A 2-kilogram mass moving along a horizontal surface at 10 meters per second is acted upon by a 5-newton force of friction. The time required to bring the mass to rest is 10 sec. 2 sec. 5 sec. 4 sec. 14. In order to keep an object weighing 20 Newtons moving at constant speed along a horizontal surface, a force of 10 Newtons is required. The force of friction between the surface and the object is 0 N 10 N 20 N 30 N 15. At a given location on the earth's surface, which graph best represents the relationship between an object's mass (M) and weight (W)? 5. What is the magnitude of the horizontal component of the ball's initial velocity? 2.5 m/s 4.3 m/s 5.0 m/s 8.7 m/s 6. As the ball rises, the vertical component of its velocity decreases increases remains the same 7. Base your answer to the following question on an object that is thrown horizontally off a cliff with an initial velocity of 5.0 m/s. The object strikes the ground 3.0 seconds later. What is the vertical speed of the object as it reaches the ground? [Neglect friction.] 130 m/s 29 m/s 15 m/s 5.0 m/s 8. Base your answer to the following question on an object that is thrown horizontally off a cliff with an initial velocity of 5.0 m/s. The object strikes the ground 3.0 seconds later. How far from the base of the cliff will the object strike the ground? [Neglect friction.] 2.9 m 9.8 m 15 m 44 m 9. Base your answer to the following question on an object that is thrown horizontally off a cliff with an initial velocity of 5.0 m/s. The object strikes the ground 3.0 seconds later. What is the horizontal speed of the object 1.0 second after it is released? [Neglect friction.] 5.0 m/s 10. m/s 15 m/s 30. m/s 10. An elevator containing a man weighing 800 Newtons is rising at a constant speed. The force exerted by the man on the floor of the elevator is less than 80 N between 80 and 800 N 800 N more than 800 N 11. An object, initially at rest, falls freely near the Earth's surface. How long does it take the object to attain a speed of 98 meters per second? 0.1 sec 10 sec 98 sec 960 sec 16. A locomotive starts from rest and accelerates at 0.12 meter per second 2 to a speed of 2.4 meters per second in 20. seconds. This motion could best be described as constant acceleration and constant velocity increasing acceleration and constant velocity constant acceleration and increasing velocity increasing acceleration and increasing velocity 17. A ball dropped from a bridge takes 3.0 seconds to reach the water below. How far is the bridge above the water? 15 m 29 m 44 m 88 m 18. A clam dropped by a sea gull takes 3.0 seconds to hit the ground. What is the sea gull's approximate height above the ground at the time the clam was dropped? 15 m 30. m 45 m 90. m 19. A book is pushed with an initial horizontal velocity of 5.0 meters per second off the top of a desk. What is the initial vertical velocity of the book? 0 m/s 2.5 m/s 5.0 m/s 10. m/s 20. A test booklet is sitting at rest on a desk. Compared to the magnitude of the force of the booklet on the desk, the magnitude of the force of the desk on the booklet is less greater the same 21. A cart is uniformly accelerating from rest. The net force acting on the cart is decreasing zero constant increasing 22. A student weighing 500. Newtons stands on a spring scale in an elevator. If the scale reads 520. Newtons, the elevator must be accelerating upward accelerating downward moving upward at constant speed moving downward at constant speed Page 1

2 23. Base your answer to the following question on Two forces are applied to a 2.0-kilogram block on a frictionless horizontal surface, as shown in the diagram below. 29. Above a flat horizontal plane, an arrow, A, is shot horizontally from a bow at a speed of 50 meters per second, as shown in the diagram below. A second arrow, B, is dropped from the same height and at the same instant as A is fired. The acceleration of the block is 5.0 m/s 2 to the right 5.0 m/s 2 to the left 3.0 m/s 2 to the right 3.0 m/s 2 to the left 24. The table below lists the coefficients of kinetic friction for four materials sliding over steel. A -kilogram block of each of these materials is pulled horizontally across a steel floor at constant velocity. Which block requires the smallest applied force to keep it moving at constant velocity? aluminum brass copper steel 25. As the mass of an object decreases, its inertia will decrease increase decreases increases remain the same 26. As the mass of a body increases, its gravitational force of attraction on the Earth remains the same Base your answers to questions 27 and 28 on the information and diagram below. Spacecraft S is traveling from planet P1 toward planet P2 At the position shown, the magnitude of the gravitational force of planet P1 on the spacecraft is equal to the magnitude of the gravitational force of planet P2 on the spacecraft. 27. As the spacecraft moves from the position shown toward planet P2, the ratio of the gravitational force of P2 on the spacecraft to the gravitational force of P 1 on the spacecraft will decrease increase remain the same 28. If distance X is greater than distance Y, then the mass of P1 must be Neglecting air friction, compared to the amount of time A takes to strike the plane, the amount of time B takes to strike the plane is less greater the same 30. The path of a satellite orbiting the Earth is best described as linear hyperbolic parabolic elliptical Base your answers to questions 31 through 35 on the diagram below which represents a ball of mass M attached to a string. The ball moves at a constant speed around a flat horizontal circle of radius R. 31. If the velocity of the ball is doubled, the centripetal acceleration is halved is doubled remains the same is quadrupled 32. When the ball is in the position shown, the direction of the centripetal force is toward point A B C D 33. The centripetal acceleration of the ball is zero constant in direction, but changing in magnitude constant in magnitude, but changing in direction changing in both magnitude and direction 34. If the string is shortened while the speed of the ball remains the same, the centripetal acceleration will decrease increase remain the same 35. If the mass of the ball is decreased, the centripetal force required to keep it moving in the same circle at the same speed decreases increases remains the same less than the mass of P2 greater than the mass of P2 equal to the mass of P2 Page 2

3 Base your answers to questions 36 and 37 on the information below: 42. Which diagram correctly shows the processes that change the states of matter? A 10.-kilogram object, starting from rest, slides down a frictionless incline with a constant acceleration of 2.0 m/sec 2 for four seconds. 36. During the 4.0 seconds, the object moves a total distance of 32 m 16 m 8.0 m 4.0 m 37. The final speed of the object after 2 seconds is. 1 m/s 2 m/s 4 m/s 8 m/s Base your answers to questions 38 through 41 on the graph below which represents the relationship between the temperature of 2.0 kilograms of a pure substance and the heat energy added to the substance. 38. The amount of heat needed to change the substance from a liquid at 50ºC to a gas at 200ºC is 150 kcal 30. kcal 15 kcal 5.0 kcal 39. The heat of fusion of the substance is 5.0 kcal/kg 2.0 kcal/kg kcal/kg ºC kcal/kg ºC 2.5 kcal/kg 50 kcal/kg 40. The specific heat of the substance in the liquid phase is 41. The freezing point of the substance is 20 kcal/kg ºC 40 kcal/kg ºC 0ºC 50ºC 150ºC 200ºC 43. The diagram below shows the isothermal pattern obtained at a height of 1 meter above the floor in a classroom during a temperature study in November. Which conclusion is best supported by this diagram? A heat source is located at A. A heat sink is located at B. Room temperature at the floor and at the ceiling can be determined. The isotherms indicate the temperatures at only one level in the room. 44. Which color is the best radiator of electromagnetic energy? red white black yellow 45. All objects warmer than 0 Kelvin (absolute zero) must be Radiating electromagnetic energy condensing to form a gas warmer than 0 Celsius expanding in size Page 3

4 46. Water is being heated in a beaker as shown below. 49. A beaker of water at 50ºC is placed in a room where the air temperature is 20ºC. Which graph best represents the change in the water temperature? Which drawing shows the most probable movement of water in the beaker due to the heating? 50. Solid X is placed in contact with solid Y. Heat will flow from X to Y if X is 20ºC and Y is 20ºC X is 10ºC and Y is 5ºC X is 25ºC and Y is 10ºC X is 25ºC and Y is 30ºC 51. Two objects, A and B, are in contact with one another. Initially, the temperature of A is 300 K and the temperature of B is 400 K. Which diagram best represents the net flow of heat in the closed system? [Arrows represent the direction of heat flow.] 47. On the graph below, the four lines show the relationship between temperature and heat added to equal masses of different metals. 52. The map below shows four locations in a temperature field. The temperature of each location is given in degrees Celsius. Which metal has the highest specific heat? A B C D 48. Which graph best shows the relationship between the average kinetic energy (KE) of a gas sample and its absolute temperature (K)? Heat energy will normally flow from A to B A to C B to D D to C 53. A cannon ball of mass 10 kg is launched at its melting point with an initial velocity of 100 m/s. If all of its kinetic energy is converted to heat energy, causing the cannon ball to completely melt but not increase in temperature, what is the latent heat of fusion of the cannon ball? 5 J/kg 10 J/kg 50 J/kg 100 J/kg E) 5 kj/kg 54. Which is a possible explanation for the fact that while energy is conserved, an object moving through air loses kinetic energy? Gravity does work on the object. The object's temperature increases. The momentum of the object decreases as it collides with the air molecules. Entropy is constantly increasing. E) Energy is not conserved. 55. A piece of metal of mass m falls from a height h. Upon hitting the ground, all of its energy is converted into heat energy that increases its temperature k degrees. What is the specific heat capacity of the metal? mgh/k gh/k gh/km mghk E) ghk 2 Page 4

5 56. Base your answer to the following question on the diagram below which shows a heating curve. If 150 J of heat are added to a mass of 5 kg between points B and C which presents an interval of 12 s, what is the latent heat of transformation for this mass at this phase change? 2.5 J/kg 12.5 J/kg 30 J/kg 62.5 J/kg E) 150 J/kg 57. As an object absorbs heat at its melting point, which of the following increases? its temperature its kinetic energy its internal energy its gravitational potential energy E) its momentum 58. The internal energy of a sample of water depends on its I. temperature II. mass III. phase I, only II, only I and II only I and III, only E) I, II, and III 59. The pressure of a sample of monatomic ideal gas is doubled at constant volume. Which of the following best describes the resulting effects? The temperature and density of the gas will both remain the same. The temperature of the gas will remain the same while the density doubles. The temperature of the gas will double while the density remains the same. The temperature and the density of the gas will both double. E) The temperature and the density of the gas will both increase by a factor of The proportion between the average kinetic energy of the molecules of a gas and the temperature of that gas is best described as linear exponential hyperbolic logarithmic E) inverse linear 61. Two large containers of equal volume each hold 1 mole of gas. Container 1 contains helium gas (4 g/mol) and container 2 contains neon gas (20 g/mol). If their pressures are equal, which of the following is true? The temperature of the gas in container 1 is greater than the temperature of the gas in container 2. The temperature of the gas in container 1 is less than the temperature of the gas in container 2. The internal energy of the gas in container 1 is greater than the internal energy of the gas in container 2. The average speed of the gas in container 1 is greater than the average speed of the gas in container 2. E) The average speed of the gas in container 1 is less than the average speed of the gas in container Work is done on an ideal monatomic gas at a constant internal energy. Which of the following is true? The temperature of the gas must decrease. The pressure of the gas must increase. There is no heat flow into or out of the gas. The average distance between particles in the gas increases. E) The pressure of the gas remains constant. 63. A heat engine operates between 400 K and a higher temperature T. What is T if the engine is 60% efficient? 160 K 240 K 600 K 1000 K E) 2400 K 64. An ideal gas undergoes an adiabatic process. Its internal energy increases by 100 J. Which of the following accurately describes the work done and heat exchanged? 100 J of work done by the process; 0 J of heat exchanged 100 J of work done on the process; 0 J of heat exchanged 100 J of work done by the process; 100 J of heat exchanged 0 J of work done on the process; 100 J of heat exchanged E) 50 J of work done on the process; 50 J of heat exchanged 65. The maximum possible efficiency for a heat engine operating between reservoirs whose temperatures are 800ºC and 600ºC is approximately 20% 25% 50% 75% E) 80% Page 5

6 Answer Key Midterm Review C 2. B 3. B 4. A 5. B 6. A 7. B 8. C 9. A 10. C 11. B 12. D 13. D 14. B 15. A 16. C 17. C 18. C 19. A 20. C 21. C 22. A 23. C 24. C 25. A 26. B 27. B 28. A 29. C 30. D 31. D 32. D 33. C 34. B 35. A 36. B 37. C 38. C 39. C 40. A 41. B 42. D 43. D 44. C 45. A 46. A 47. D 48. B 49. D 50. B 51. D 52. A 53. E 54. B 55. B 56. C 57. C 58. E 59. C 60. A 61. D 62. B 63. D 64. B 65. A Page 6