Exam 1

Question 1

Biomechanices

Answer 1

is the study f forces and their effect on living systmes

Question 2

what are the goals f sports biomechanics

Answer 2

1 performance improvement

2 injury prevention

Question 3

Statics

Answer 3

the study of systems that are in a state of constant motion either at rest or moving with a constant velocity

Question 4

Dynamics

Answer 4

the study of systems in motion in which acceleratin is present,which may involve, kinematics or kinetics

Question 5

kinematics

Answer 5

the study of motion of bodies with respect to time, displacement, velocity, and speed of movement either in a straight line or in a rotary direction

Question 6

Kinetics

Answer 6

the study of the forces associated with motion

Question 7

Two approaches to biome.

Answer 7

qualitative and quantitative

Question 8

qualitative

Answer 8

movement is described without the use of numbers

- coaches relay on this

Question 9

quantitative

Answer 9

numbers are involved

Question 10

biomechanical analyses can be divided into 4 areas

Answer 10

1 noncinematographic- naked eye, no numbers
2 basic cinematographic - using visual recording, no #
3 intermediate cinematgraph- using numbers with a camera
4 biomechanics research- using high speed cameras, will have high end #

Question 11

Force

Answer 11

-is a push or a pull exerted by obect on other objects
these forces come in pairs
-force is a vector quantit

Question 12

1 N

1 pound

Answer 12

1 N= (1kg) * (1 m/s^2)

1 pound = (1 slug) * (1 ft/s^2)

Question 13

gravity (g) =

Answer 13

9. 81 m/s^2

32. 2 ft/s^2

Question 14

weight =

Answer 14

weight= mass * (g)

Question 15

contact forces

Answer 15

act perpendicular ( normal reaction force) and parallel to the surfaces in contact ( friction)

Question 16

Friction

Answer 16

• • friction is proportional to the normal contact force and acts perpendicular to it
• static friction
• dynamic friction
• fluid friction

Question 17

static friction

Answer 17

is dry friction that acts between two surfaces that are not moving relative to each other

Question 18

dynamic friction

Answer 18

is dry friction that acts between two surfaces that are moving relative to each other

Question 19

fluid friction

Answer 19

develops between tow layers of fluid

Question 20

friction and surface area

Answer 20

-if ↑ F is applied that more molecular interaction will be↑ and F will ↑
- BUT if F is the same and surface area is ↑ the F is spread over a larger area which will ↓ the pressure
pressure = F/area

Question 21

types of contacting materials

Answer 21

softer and rugher surfaces over harder and smoother surfaces will create more Friction

Question 22

friction equations

Answer 22

F=mR

Question 23

Equation

Answer 23

a^2+b^2=c^2
sin = opp/ hyp
cos = adj/ hyp
tan= opp/adj

Question 24

Linear motion

Answer 24

all points on a body move the same distance, in the same direction and at the same time.

Question 25

rectilinear translation

Answer 25

straight line- direction of motion does not change, orientation of the object does not change, all points of the object move the same distance

Question 26

curvilinear translation

Answer 26

curved path- orientation of the object does not change, all points of the object move the same distance but the dircetion of motion of the object is constantly changing

Question 27

angular motion

Answer 27

all points of a body move in a circle bout a fixed axis

Question 28

general motion

Answer 28

a combination of linear and angular motion

Question 29

kinematics

Answer 29

a branch of dynamics concerned with the description of motion

Question 30

position

Answer 30

location in space
one - only one # is needed
two- x and y coordinates
three-x,y,z uses three axes

Question 31

distance traveled

Answer 31

is the length of the path of the object, scalar quantity

Question 32

displacement

Answer 32

is the straight-line distance in a specific direction from the initial postilion to the final position, vector quantity

Question 33

speed

Answer 33

is a rate of motion; measure of the rate of change is position/ unit of time

Question 34

velocity

Answer 34

is rate of motion in a specific direction, rate of displacement

Question 35

average speed or average velocity

Answer 35

measure over a very small interval of time

Question 36

acceleration

Answer 36

is the rate of change of velocity m/s^2

• positive- upward or speeding up
• negative- slowing down or downward

Question 37

projectile motion

Answer 37

when an object is thrown into the air

• time of flight
• max height
• range

Question 38

parabolic trajectories

Answer 38

you want to calclate velocity components of t, h and r