Example #13: A student conducts an experiment in which an object is released from rest above a motion detector so that data can be collected about the object's motion as the object falls to the ground. The experiment is conducted near Earth's surface. All frictional forces are considered to be negligible unless otherwise stated. 3000 2500+ 2000- Kinetic Energy (J) 1500+ 1000-+ 500+ 6 Time (s) The student collects the data necessary to graph the object's kinetic energy as a function of time, as shown. Which of the following graphs represents the sum of the kinetic energy K and gravitational potential energy U, of the object-Earth system as a function of time? (Click HERE to verify your answer). 3000 3000 2500- C. a. 2500 2000- 2000- 1500- + Ugl 1500 1000- 1000- 500- 500- 04 2 2 Time (s) Time (s) Y 3000- 3000- b. 2500 2 2000- 2500- 32000 1500- K + U. () K+ 1500- 1000- 1000- 500 500- 2 4 2 4 Time (s) Time (s)Example #17: MULTIPLE CORRECT: A block of mass M is at rest on a ramp that is inclined at an angle 0 with respect to the horizontal. Frictional forces are considered to be nonnegligible. The block is pushed against a spring and then held in place. The spring is compressed a distance of x1, and the spring is not secured to the block. The block is then released from rest, travels up the incline, and comes to rest after traveling a distance D, as shown below. D Which of the following claims correctly describes the energy of the system under consideration from when the block compressed the spring and when the block has traveled a distance D along the incline? Select two answers. (Click HERE to verify your answers). a. The mechanical energy of the system consisting of the spring increases by -? b. The mechanical energy of the system consisting of the block does not change. c. The mechanical energy of the system consisting of the block and Earth increases by more than zero but less than x 2 d. The mechanical energy of the system consisting of the spring, block, and Earth increases by 2 24Example #13: MULTIPLE CORRECT: Arr inclined hack is secured la a |able.Thet1eigl1| at Ihe Trigtresl point of the track above The tabletop is hi. The height from the tabletoo to the oor is THE. A block at mass M is released from rest and slides down the track such That all frictional forces are considered to be negligible. The block leaves the track horizontally and strikes the ground at a distance D from the edge of the Track as shown. Which of the following statements is correct about the scenario? Select Two answers. {Click HERE to verifg 50hr answers]. a. It the block is released from a height 2&1. The block will land at a distance 29 away from the end of the track. b. It the block's mass is increased to EN. the black will land at a distance ED away from the edge of The track. c. The total mechanical energy of the system containing only the black increases from The moment at release to the moment it strikes the ground. d. The total mechanical energy of the block-Earth system remains constant