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The following physics responses are provided by a student and, as such, should be considered in that context. While every effort is made for accuracy, absolute correctness cannot be fully guaranteed.

C | I | Question | Answer |
---|---|---|---|

6 | A 1.00-kg duck is flying overhead at 1.50 m/s when a hunter fires straight up. The 0.010 0-kg bullet is moving 100 m/s when it hits the duck and stays lodged in the duck's body. What is the speed of the duck and bullet immediately after the hit? | 1.78 m/s | |

8 | A bucket of water with total mass 23 kg is attached to a rope, which in turn is wound around a 0.050-m radius cylinder, with crank, at the top of a well. The moment of inertia of the cylinder and crank is 0.12 kg*m^2. The bucket is raised to the top of the well and released to fall back into the well. What is the kinetic energy of the cylinder and crank at the instant the bucket is moving with a speed of 8.0 m/s? | 1.5*10^3 J | |

11 | Of the following systems, which contains the most heat? | Systems do not contain heat. | |

4 | A trapeze artist, with swing, weighs 800 N; he is momentarily held to one side by his partner so that the swing ropes make an angle of 30.0° with the vertical. In such a condition of static equilibrium, what is the horizontal force being applied by the partner? | 462N | |

6 | In a two-body collision, if the momentum of the system is conserved, then which of the following best describes the kinetic energy after the collision? | may also be conserved | |

8 | If a net torque is applied to an object, that object will experience: | an angular acceleration. | |

11 | Which of the following involves the greatest heat transfer? | One gram of steam at 100°C changing to water at 100°C. | |

4 | A 2 000-kg sailboat experiences an eastward force of 3 000 N by the ocean tide and a wind force against its sails with magnitude of 6 000 N directed toward the northwest (45° N of W). What is the direction of the resultant acceleration? | 74° N of W | |

6 | If a glass of water is on a table with a piece of paper under it, it is relatively easy to pull the paper out without disturbing the glass very much if the pull is done very quickly. This is because, with a quick pull: | the time for the pull will be less. | |

8 | A rod of length L is pivoted about its left end and has a force F applied perpendicular to the other end. The force F is now removed and another force F' is applied at the midpoint of the rod. If F' is at an angle of 30° with respect to the rod, what is its magnitude if the resulting torque is the same as when F was applied? | 4F | |

11 | A metal bar is used to conduct heat. When the temperature at one end is 100°C and at the other is 20°C, heat is transferred at a rate of 16 J/s. The bar is then stretched uniformly to twice its original length. If again it has ends at 100°C and 20°C, at what rate will heat be transferred between it ends? | 4 J/s | |

4 | Three identical 6.0-kg cubes are placed on a horizontal frictionless surface in contact with one another. The cubes are lined up from left to right and a 36-N force is applied to the left side of the left cube causing all three cubes to accelerate to the right. If the cubes are each subject to a frictional force of 6.0 N, what is the magnitude of the force exerted on the right cube by the middle cube in this case? | 12N | |

6 | If a two-body collision is not head-on, then we may always assume that: | momentum is conserved. | |

8 | An 800-N billboard worker stands on a 4.0-m scaffold supported by vertical ropes at each end. If the scaffold weighs 500 N and the worker stands 1.0 m from one end, what is the tension in the rope nearest the worker? | 850 N | |

11 | The first experiment, which systematically demonstrated the equivalence of mechanical energy and heat, was performed by: | Joule |