week 6 biomechanics

Question 1

what is biomechanics?

Answer 1

application of mechanical laws onto living structures
- specifically, the locomotor system of the human body

Question 2

why do we conduct biomedical analyses?

Answer 2

• helps us improve skill techniques, design sports equipment, prevent injuries, help heal injuries, and prostheses, animations

Question 3

what is qualitative movement analysis?

Answer 3

non-numerical description of a movement based on observation

Question 4

quantitative movement analysis?

Answer 4

a movement that is analyzed numerically based on measurements from data collected
- generally researchers

Question 5

what is mass and its unit

Answer 5

the quantity of matter contained in an object
- kg

Question 6

what is force and its unit

Answer 6

mass x acceleration
unit = newtons

Question 7

what is weight and its unit?

Answer 7

the amount of grvaity force exerted on a body
mass x acceleration

Question 8

what is gravity

Answer 8

9.81m/s^2

Question 9

what is volume

Answer 9

the amount of space that a body occupies

Question 10

what is pressure

Answer 10

force distributed over a given area
pressure = F/A

Question 11

what is compression

Answer 11

pressing or squeezing force directly axially through body

Question 12

what is tension

Answer 12

pulling or stretching force directly axially through a body

Question 13

what is shear

Answer 13

force directed parallel to a surface

Question 14

what is a lever

Answer 14

a rigid bar that turns an axis

Question 15

what is the force point

Answer 15

the point where effort is applied (muscle insertion)

Question 16

what is the resistance point R

Answer 16

the exact point on which the resistance acts

Question 17

what is the fulcrum

Answer 17

the axis of rotation

Question 18

where is the resistance in the first, second and third class leavers

Answer 18

first class - first
second class - second (between)
third class - last

Question 19

what is a first class lever +example

Answer 19

fulcrum is between force point and resistance
- teeter totter

Question 20

what is a second-class lever +example

Answer 20

resistance in middle and force and fulcrum on outside
wheel barrow

Question 21

what is a third-class level + example

Answer 21

resistance at end, force in middle, fulcrum front
- most common in body

Question 22

what does a third class level permit?

Answer 22

muscle inserted near the joint to produce distance and speed of movement
- however at the sacrifice of force

Question 23

what is the mechanical advantage of levers

Answer 23

the ratio of force arm length to resistance arm length

Question 24

what does a longer resistance arm give you

Answer 24

a speed lever - more speed but less force

Question 25

what happens when force arm of level is longer than resistance

Answer 25

we get a force arm , mechanical advantage favours force

Question 26

what is the mechanical advantage formula

Answer 26

force arm divided by resistance arm

Question 27

what is a moment arm

Answer 27

perpedicular distance between force's line of action and the axis of rotation -

Question 28

what is the center of gravity

Answer 28

the axis where you have equal weight balanced in all directions of your body the center of your mass - intersection of frontal, transverse and sagittal planes

Question 29

where approximately is the center of gravity and why does this vary

Answer 29

generally around or below the belly button varies depending on the proportions

Question 30

why is it useful to determine center of gravity

Answer 30

helps for stability movement in space important in factor in calculating work done

Question 31

how can you increase stability

Answer 31

increase mass increase base lower center of gravity lean into force

Question 32

what is issac newtons first law

Answer 32

the law of inertia - body will maintain state of rest or constant velocity unless acted on by a force - amount of inertia body has Is related to the amount of mass

Question 33

the more force...

Answer 33

the more acceleration

Question 34

what is the second law

Answer 34

the law of acceleration force = mass x acceleration

Question 35

what is the third law

Answer 35

law of reaction when one body exerts force on second body the second body exerts reaction force that is equal in magnitude but opposite in direction of the first body

Question 36

how to u calculate momentum

Answer 36

mass x velocity

Question 37

what is momentum

Answer 37

the quantity of motion that an object possesses

Question 38

what is the work formula

Answer 38

force x distance

Question 39

what is the work power relationships formulas plus unit of power

Answer 39

power = work per unit of time power = (force x distance) divided by time unit = watts

Question 40

what are the differences between walking and running? what is more efficient?

Answer 40

running is generally faster, both feet off ground efficiency depends on velocity, if running fast its more efficient but if running slow it is not

Question 41

running is a series of...

Answer 41

jumps

Question 42

what does running speed depend on

Answer 42

the stride length x stride rate

Question 43

what does length of stride depend on

Answer 43

leg length and power of stride

Question 44

what does leg speed depend on

Answer 44

speed of muscle contraction and neuromuscular coordination (skill) in running