EXSC 550 Exam 2

EXSC 550 Exam 2 Liberty University

1. Which of Newton’s laws is most closely related to ground reaction forces?
2. You are using 2D video analysis software to measure an athlete’s knee flexion ROM during a squat (from the sagittal view). You decide to measure the ROM as an absolute angle rather than a relative angle. How would you best measure an absolute angle of the knee based on the choices below?
3. A sprinter leaves the blocks in a 100m race and has just begun running in a positive direction toward the finish line. The athlete’s movement yields magnitude of
4. In order for a 2D kinematic analysis of an athlete’s motion to be performed, what is the minimum number of points that must be quantified for each body segment analyzed?
5. The occipito-atlanto joint in the body is an example of which lever system?
6. According to the study by Khadilkar, what is the minimum amount of shoulder range of motion (ROM) necessary to perform daily living tasks?
7. Degrees of freedom can be defined as a direction in which independent motion can occur. An object that is analyzed in 2D has how many degrees of freedom?
8. What set of mathematical operations can be performed to calculate joint reaction forces (JRFs) using an individual’s acceleration and mass?
9. The biomechanical term for linear motion is:
10. According to the article by Okazaki, as a basketball player shoots a basketball from greater distances, other than aim, what biomechanical factors contribute to the reduction in shot accuracy when compared to shooting at close distances?
11. When an athlete is slowing down in a positive direction, such as after crossing a finish line in the 100m dash .
12. What type of diagram is shown above?
13. Which of the following is false regarding center of pressure (COP) measurement?
14. Which term refers to the resistance that an object offers to a change in its state of motion (or direction of motion) and is directly related to its mass?
15. Which of the following is false regarding joint reaction forces (JRF’s)?
16. The location on the forceplate at which the GRF acts through is known as the:
17. A figure skater performs a 2 ½ revolution spin. What was her angular displacement in revolutions?
18. You are performing research in the biomechanics lab and you want to compare the angular impulses generated between two different types of jumping techniques in order to compare the angular momentum that they generate. What two components make up angular impulse?
19. According to the review article on the biomechanics of swim-starts by Vantorre, in studies which compared elite versus novice swimmers, which group has higher take-off angles off the block?
20. A horizontally oriented force that causes a runner to decelerate when their foot strikes the ground at heel contact is known as:
21. This lever system positions the fulcrum between the force of muscle effort and the resistive force. It can also be represented by a “see-saw” in which forces act in the same direction on opposite sides of the fulcrum.
22. The calf raise exercise represents what type of lever system?
23. In the biomechanics lab, you are analyzing 3D forces during a jump landing on a force plate. Which variable would you analyze to determine the twisting moment (how much vertical torque occurred) when the athlete landed on the force plate?
24. What type of force are you analyzing when you are investigating the turning effect on an object by which torque was applied. For example, the force that caused the soccer ball to “bend” or “curve” in the air after it was kicked.
25. The moment of inertia of the leg during a running is highest when:
26. Which of the following is false in regards to the article by Pappas?
27. Which of the following is true regarding the relationship between linear and angular motion?
28. You are coaching a young softball player who is struggling with being able to swing the bat with enough speed in order to hit the ball. You instruct her to “choke up” on the bat by moving her hand position higher on the bat. By doing this, what effect did this have on the bat’s moment of inertia?
29. Up to how many planes of movement can a force plate measure?
30. You are about to perform a 3D analysis in the lab using cameras and force plates. The cameras are set to record at a rate of 100 Hz and the force plates are set to record at a rate of 1000 Hz. True or false: The cameras and force plates must be set to the same recording rate in order for proper synchronization of kinematic and kinetic data to occur.
31. In sports biomechanics labs, mediolateral force is measured along which axis of the force plate?
32. In biomechanics, clockwise rotation is considered positive rotation, while counterclockwise rotation is considered negative rotation.
33. Which of the following statements is true regarding the graph above?
34. What type of device can be used during rehabilitation or biomechanical research to accurately measure torque production by keeping an individual’s speed of movement
35. This lever system is the most common lever system in our bodies as it assists us in moving quickly and through large ranges of motion. In this lever system, the fulcrum is located at one end of the lever and the resistive force is located at the opposite end. The force of muscle effort is located between the fulcrum and resistance force.
36. The equation for pressure is:
37. As discussed in the article by Pappas, what is the most dangerous phase of landing which often produces the ACL tear when an athlete lands with poor mechanics?
38. is determined by multiplying force by distance.
39. You are analyzing a softball pitch with video analysis. As the ball is traveling in a circular path during the windmill pitching technique, the ball is traveling with a specific angular velocity, however at the point of release from the pitcher’s hand, angular velocity is converted to velocity as it travels toward home plate.
40. To calculate , which is used to assess the severity of impacts and collisions in sports,   is divided by the time period that the collision occurred.
41. You are performing a 3D gait analysis in the biomechanics lab. A subject is walking across a force plate. When is the subject’s center of pressure (COP) located between both of the subject’s feet?
42. A track and field athlete just completed the 400 meter dash on the track. From start to finish, this athlete’s displacement was zero.
43. Velocity equals:
44. According to the review article on the biomechanics of swim-starts by Vantorre, what is/are essential biomechanical component(s) of the glide phase of the swim start?
45. is calculated by multiplying mass by velocity.
46. Which is a value defining the rate of change of velocity?
47. Power = force x , divided by
48. What is determined when force and moment arm are multiplied by each other?
49. Which unit can be represented with a vector?
50. Which is false regarding angles measured biomechanically and angles measured medically (clinically)?
51. According to the article by Okazaki, during which phase of the basketball jump shot does the basketball player typically release the ball when shooting from intermediate and
52. long distances?
53. Which statement is true regarding linear motion?
54. Regarding the research study by Khadilkar which investigated shoulder ROM during activities of daily living (ADL’s), which of the following is true regarding their findings?
55. You are observing sagittal plane movement of an athlete’s lower extremity during a maximal vertical jump test. As the athlete “explodes” upward into the air during the test, their lower extremity joints extend. When analyzing the hip, knee, and ankle jointswith video analysis, which of the following is true regarding the analysis of the concentric (explosive) phase of the jump?
56. Which of the following is false when comparing the gait cycle of an athlete who is sprinting compared to an athlete who is walking?
57. Angular acceleration of a body is proportional to net torque applied, while angular acceleration is      proportional to rotational inertia.
58. Describe the proper procedures involved in order to set up and record a video of a subject to be used for 2D biomechanical analysis. Also, briefly discuss how to download this video into the Dartfish software based on the information provided in the 2D video analysis presentation.