16) Julie carries an 8.0-kg suitcase as she walks 18 m along a horizontal walkway to her hotel room at a constant speed of 1.5 m/s. How much work does Julie do in carrying her suitcase? (A) 200 J. (B) 40 J. (C) 0J. (D) 300 J. (E) 2000 J 17) Which one of the following situations is an example of an object with a non-zero kinetic energy? (A) a drum of diesel fuel on a parked truck (B) a stationary pendulum (C) a boulder resting at the bottom of a cliff (D) a car parked at the top of a hill (E) a satellite in geosynchronous orbit 18) How much energy is dissipated in braking a 1500-kg car to a stop from an initial speed of 30 m/s? A) 24 KJ B) 675 kJ C) 280 KJ D) 820 kJ E) 12 KJ 19) The radii of two wheels are r, = 0.50 m and r2 = 0.20 m. If the same force is applied in the same direction to each wheel, what is the ratio 71/72 of the torques produced by this force on the two wheels? (A) 2.5 (B) 1.0 (C) 1.5 (D) 0.4 (E) 15 20) Consider the following four objects: a hoop, a flat disk, a solid sphere, and a hollow sphere. Each of the objects has mass M and radius R. The axis of rotation passes through the center of each object, and is perpendicular to the plane of the hoop and the plane of the flat disk. Which of these objects requires the largest torque to give it the same angular acceleration? (A) the solid sphere (B) the hollow sphere (C) the hoop (D) the flat disk (E) both the solid and the hollow spheres