Biomechanics – Study Guide #1
Use only metric answers.
1. An offensive lineman for a professional football team has a body mass of 150kg
and a height of 203cm. What is the football player’s BMI? Why is this BMI
value not necessarily a bad thing for the football player?
2. Briefly explain the crural index and provide an example of an athlete or animal in
which it is high.
3. What is the plane in which a runner’s arms move?
4. Around which axis does the shoulder joint move as the arms move in the above
5. If I drop an object from a small height, what type of motion will it exhibit? What
motion will the object exhibit if I throw it?
6. Is running motion considered to be translation, rotation, or general? Which of
these types of motion is bicycling considered? Explain your answers?
7. Name a skill that is an example of a complex and open kinetic chain?
8. θ = 30º
a. What is the radius of rotation for point A? Point B? Point C?
b. Which point has the greatest angular displacement? What is that angular
c. Which point has the greatest linear displacement?
9. In what units are mass and weight measured? Why are they not the same?
10. Where could I go and my weight would change, but my mass would stay the
11. Name the 5 properties of a force and give very brief definitions of each of them.
12. What can be used to represent a force?
13. What does the length of a vector represent?
14. What does the arrow point of a vector represent?
15. What does the tail of a vector represent?
16. What 2 components can a muscle force be resolved into? What function does
each of these perform?
17. What are the values of the magnitude of the 2 components in the following
problems? (you must use a ruler, be neat and draw straight lines, be sure to make
your lines as perfectly perpendicular and parallel as possible when necessary,
make sure your vectors have an arrow and the arrow is pointed in the proper
direction, and show all your work even if it is simple)?
1cm = 20N
18. Interpret the answers to question #17.
19. What is the magnitude of the resultant vector in the following problems (you must
use a ruler, be neat and draw straight lines, be sure to make your lines as perfectly
perpendicular and parallel as possible when necessary, make sure your vectors
have an arrow and the arrow is pointed in the proper direction, and show all your
work even if it is simple)?
1cm = 100N
20. Explain the Q-angle. Give some normal values of the Q-angle. What are the
consequences of an abnormally large value?