 PhysicsBowl 2013 (Part 2) Printer Friendly Version
26. An object moving only to the right completes a 20.0 second trip in two stages, I and II. The average speed of the entire second trip is 20.0 m/s. For stage I, the object moves with a constant velocity of 6.0 m/s for 12.0 seconds. What constant acceleration must the object have during the seconds of stage II? 27. Light of wavelength is transmitted from air into a piece of glass. Which one of the labeled arrows best indicates the path of the light ray after it enters the glass?   needs image
28. An object is in free fall close to the ground. A person intervenes and slows the object uniformly to rest. Which one of the following statements must be true about the magnitude of the acceleration of the object as it is being stopped by the person? The magnitude of the object’s acceleration is aobj and the magnitude of the acceleration from gravity is g. 29. Two electrons enter a region between charged capacitor plates with equal speed v. Electron A is directed horizontally to the left while electron B is directed at 30º below the horizontal. Each electron makes it to the left-hand plate. Which one of the following choices best compares the speeds of the charges (vA, vB) upon arrival at the left plate? Consider only the electrons A and B’s interactions with the constant electric field between the plates, ignoring any relativistic effects. 30. Electrons flow to the left in a wire as shown. For the proton moving toward the top of the page at the instant shown, what is the direction of the magnetic force on the proton?
31. A monatomic ideal gas undergoes a reversible isothermal expansion in an enclosed container. Which one of the following quantities associated with the gas has a value of zero?
32. An acceleration vs. time graph for an object moving along a line is shown. The object starts from rest at time t = 0 s. At what time(s) does the object attain a maximum displacement from its starting position? 33. At the top of a high cliff, a small rock is dropped from rest. A ball is launched straight downward with an initial speed of 36.0 m/s at a time t = 2.10 s after the rock was dropped. When the ball has fallen 28.0 m further than the initially dropped rock, what is the speed of the ball relative to the rock?
34. Which one of the following choices represents the base MKS units for sound intensity? 35. For the figure shown, the variable resistance of the inner circuit, Rinner, is increasing at a constant rate. While this is occurring, in which direction is the magnetic field associated with the inner circuit at the point P in the plane of the circuit and in which direction is the flow of electrons through the resistor labeled Router? 36. The principal quantum number of an electron is n = 5. How many possible values of the orbital magnetic quantum number ml are there for this electron?
37. A real object in air is placed in front of a glass lens. The calculated image size is larger than the size of the original object. Which one of the following conclusions about the type of lens used and the type of image formed is correct?  38. Five identical light bulbs are connected into a circuit as shown. All wires are ideal with no resistance, and the ideal battery has When the switch S in the circuit is closed, aside from bulb #5, which of the other bulbs brighten?

The next two questions share the same information Base your answers to questions 39 and 40 on the information and diagram below.

 An ideal uniform solid disk and an ideal uniform ring each have mass M and radius R. Each object begins purely rolling without slipping down a rough inclined plane. The coefficients of friction for the disk and ring with the incline are µdisk > µring. 39. As each object rolls down the incline, which statement is correct about the force of friction from the incline on the objects?

40. As the objects roll, what is the ratio of the ring’s angular acceleration to the disk’s angular acceleration calculated about an axis perpendicular to the object’s face and through its center of mass?

All Division 01 students STOP HERE. Your last answer should be for #40. Numbers #41-#50 should remain blank for Division 01 students.
All Division 02 students continue to Questions #41 – #50.

41. An engine operates between a low temperature of 273 ºC and a high temperature of 546 ºC. What is the maximum theoretical efficiency of this engine? 42. An object of mass 12M is at rest when it suddenly explodes into 3 pieces with masses 3M, 4M, and 5M. The piece of mass 3M moves with speed V in the direction shown in the diagram. What is the speed of the piece with mass 5M knowing that it is moving directly to the right?
43. A small 1.0 kg mass is launched from the top of a cliff with speed V at an angle of 30º above the horizontal. When the mass reaches the ground, its velocity is directed at 45º below the horizontal. Which one of the following choices is the magnitude of the total impulse that was imparted to the mass during its flight? Ignore air resistance.
44. Which one of the following terms/quantities is most closely associated with “the measure of the resistance of an object to length change under lengthwise tension or compression.”? 45. The switch in the RC circuit shown is closed at time t = 0. All circuit elements are ideal and R = 10.0 ohms, C = 2.20 F and The capacitor is initially uncharged. How long after the switch is closed is the voltage across the capacitor three times as large as the voltage across the resistor?
46. Which one of the following quarks was the last to be confirmed experimentally?
47. Which one of the following choices best represents the magnitude of the angular momentum of the Earth (expressed in base MKS units) associated with its rotation about its axis?
48. Two identical samples of a monatomic ideal gas are to undergo reversible processes. Which one of the following choices is a correct statement about the heat associated with the processes?

• Process 1: An isochoric pressure doubling
• Process 2: An isobaric volume doubling

49. Two electrons move with the magnitude of their linear momentum having a ratio of 2:1. If the slower electron moves with a speed of 1.20 x 108 m/s, what is the speed of the faster moving electron? 50. A U-tube is filled with mercury (density 13.6 g⁄cm3) as shown in the left-most figure. Water of mass 800 grams is added to the left-hand side of the tube. When equilibrium is re-established, the tube appears as shown in the right-most figure. The cross-sectional area of the left tube is 6.50 cm2 while the right tube has cross-sectional area 15.0 cm2. Which one of the following choices best represents the height x above the original equilibrium that the mercury rises in the right tube? The drawings are not to scale.

All Division 02 students STOP HERE. Your last answer should be for #50. Related Documents