Physics Mc Practice free essay sample

The drawing shows three containers filled to the same height with the same fluid. In which container, if any, is the pressure at the bottom greatest? (a) Container A, because its bottom has the greatest surface area. (b) All three containers have the same pressure at the bottom. (c) Container A, because it has the greatest volume of fluid. (d) Container B, because it has the least volume of fluid. (e) Container C, because its bottom has the least surface area. 2. Three solid objects are floating in a liquid, as in the drawing. They have different weights and volumes, but have the same thickness (the dimension perpendicular to the page). Rank the objects according to their density, largest first. (a) A, B, C (b) A, C, B (c) B, A, C (d) B, C, A (e) C, A, B 3. The kinetic energy of an object attached to a horizontal ideal spring is denoted by KE and the elastic potential energy by PE. We will write a custom essay sample on Physics Mc Practice or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page For the simple harmonic motion of this object the maximum kinetic energy and the maximum elastic potential energy during an oscillation cycle are KEmax and PEmax , respectively. In the absence of friction, air resistance, and any other nonconservative forces, which of the following equations applies to the object–spring system? A. KE+PE = constant B. KEmax = PEmax (a) A, but not B (b) B, but not A (c) A and B (d) Neither A nor B 4. The drawing shows three objects rotating about a vertical axis. The mass of each object is given in terms of m0 , and its perpendicular distance from the axis is specified in terms of r0. Rank the three objects according to their moments of inertia, largest to smallest. (a) A, B, C (b) A, C, B (c) B, A, C (d) B, C, A (e) C, A, B 5. The drawing illustrates an overhead view of a door and its axis of rotation. The axis is perpendicular to the page. There are four forces acting on the door, and they have the same magnitude. Rank the torque ? that each force produces, largest to smallest. (a) (b) (c) (d) (e) ? 4 , ? 3 , ? 2 , ? 1 ? 3 , ? 2 , ? 1 and ? 4 (a two-way tie) ? 2 , ? 4 , ? 3 , ? 1 ? 1 , ? 4 , ? 3 , ? 2 ? 2 , ? 3 and ? 4 (a two-way tie), ? 1 6. Two points are located on a rigid wheel that is rotating with a decreasing angular velocity about a fixed axis. Point A is located on the rim of the wheel and point B is halfway between the rim and the axis. Which one of the following statements is true concerning this situation? (a) Both points have the same centripetal acceleration. (b) Both points have the same tangential acceleration. (c) The angular velocity at point A is greater than that of point B. (d) Both points have the same instantaneous angular velocity. (e) Each second, point A turns through a greater angle than point B. 7. Two identical cars are traveling at the same speed. One is heading due east and the other due north, as the drawing shows. Which statement is true regarding the kinetic energies and momenta of the cars? (a) They both have the same kinetic energies and the same momenta. (b) They have the same kinetic energies, but different momenta. (c) They have different kinetic energies, but the same momenta. (d) They have different kinetic energies and different momenta. 8. The same force F pushes in three different ways on a box moving with a velocity v, as the drawings show. Rank the work done by the force F in ascending order (smallest first): (a) A, B, C (b) A, C, B (c) B, A, C (d) C, A, B (e) B, C, A 9. In which one of the following circumstances could mechanical energy not possibly be conserved, even if friction and air resistance are absent? (a) A car moves up a hill, its velocity continually decreasing along the way. (b) A car moves down a hill, its velocity continually increasing along the way. (c) A car moves along level ground at a constant velocity. (d) A car moves up a hill at a constant velocity. 10. The drawings show three examples of the force with which someone pushes against a vertical wall. In each case the magnitude of the pushing force is the same. Rank the normal forces that the wall applies to the pusher in ascending order (smallest first). (a) C, B, A (b) B, A, C (c) A, C, B (d) B, C, A (e) C, A, B 11. Three identical blocks are being pulled or pushed across a horizontal surface by a force F, as shown in the drawings. The force F in each case has the same magnitude. Rank the kinetic frictional forces that act on the blocks in ascending order (smallest first). (a) B, C, A (b) C, A, B (c) B, A, C (d) C, B, A (e) A, C, B 12. An object is moving at a constant velocity. All but one of the following statements could be true. Which one cannot be true? (a) No forces act on the object. (b) A single force acts on the object. (c) Two forces act simultaneously on the object. (d) Three forces act simultaneously on the object. 13. Each drawing shows three points along the path of a projectile, one on its way up, one at the top, and one on its way down. The launch point is on the left in each drawing. Which drawing correctly represents the acceleration a of the projectile at these three points? (a) 1 (b) 2 (c) 3 (d) 4 (e) 5 14. (a) (b) (c) (d) (e) 15. Two objects A and B accelerate from rest with the same constant acceleration. Object A accelerates for twice as much time as object B, however. Which one of the following statements is true concerning these objects at the end of their respective periods of acceleration? (a) Object A will travel twice as far as object B. (b) Object A will travel four times as far as object B. (c) Object A will travel eight times further than object B. (d) Object A will be moving four times faster than object B. (e) Object A will be moving eight times faster than object B. 16. Which one of the following statements concerning the moment of inertia I is false? I may be expressed in units of kg †¢ m2. (b) I depends on the angular acceleration of the object as it rotates. (c) I depends on the location of the rotation axis relative to the particles that make up the object. (d) I depends on the orientation of the rotation axis relative to the particles that make up the object. (e) Of the particles that make up an object, the particle with the smallest mass may contribute the greatest amount to I. 17. A wrecking ball attached to the end of a long, essentially massless chain is released from rest, from a height H = 5 meters off the ground, as shown in figure 1. At the lowest point of its swing, it collides with a piece of modern sculpture. Since the sculpture is made of wet clay, it sticks to the wrecking ball. The wrecking ball has mass 200 kg. The sculpture has mass 100 kg. During the collision the mechanical energy of the whole system: (a) increases (b) decreases (c) stays same (d) cannot be determined 18. Two identical satellites are in orbit about the earth. One orbit has a radius r and the other 2r. The centripetal force on the satellite in the larger orbit is as that on the satellite in the smaller orbit. The apparent weight of a passenger in an elevator is greater than his true weight. Which one of the following is true? (a) The elevator is either moving upward with an increasing speed or moving upward with a decreasing speed. (b) The elevator is either moving upward with an increasing speed or moving downward with an increasing speed. (c) The elevator is either moving upward with a decreasing speed or moving downward with a decreasing speed. The elevator is either moving upward with an increasing speed or moving downward with a decreasing speed. (e) The elevator is either moving upward with a decreasing speed or moving downward with an increasing speed. 20. What is the difference between distance and displacement? (a) Distance is a vector, while displacement is not a vector. (b) Displacement is a vector, while distance is not a vector. (c) There is no difference between the two concepts; they may be used interchangeably. (d) Only Physicsts know the difference, but there really isn’t any practical difference between the two.