Biomechanics Final Exam broski

the moment arm in a torque equation is the _______ distance between the action line of the applied force and the axis of rotation

perpendicular

the proximal radioulnar joint is an example of a ________ joint

pivot

potential energy is due to _________

position

performing a chin-up is an example of _________ work (on the way up)

positive

______ energy = m x g x h

potential

muscular strength is a function of

pre-stretch size fiber type

when one who is standing in the anatomical neutral position, rotates at the hip internally (turning thigh medially), the leg is moving around what axis?

proximal to distal

which of the following is an example of amphiarthrosis

pubic symphysis

the event during an action potential where the voltage re-stabilies

repolarization

when one who is standing in the anatomical neutral position, brings his/her knee towards their chest by moving at the hip, the femur is moving predominantly in what plane

saggital

a patient performing seated knee flexion/extension exercises is moving their leg in which plane

sagittal

functional unit of a muscle

sarcomere

muscle degeneration/wasting that occurs with age is called _______

sarcopenia

which of the following is an example of a synarthrosis

skull sutures

____ can be thought of as the magnitude of velocity

speed

mechanical property equal to force divided by cross sectional area

stress

power =

work/time

_______ is a measure of the elasticity of the material and is he slope of the linear portion of a stress-strain plot

youngs modulus

the ________ of the spinal segments dictate the available range of motion at that segment

zygopophyseal joints facet joints

change in momentum is = to ______

impulse

deposition of new bone

osteoblaslt

the _______ is the outer covering of an intervertebral disc

annulus fibrosis

which of the following is an example of a pivot joint

atlantoaxial (head/neck)

intervertebral discs are

avascular

which of the following are responsible for depositing new bone

osteoblast

the _______ of the neuron carries the electrical impulse away from the cell body and may be covered by schwann cells

axon

in order for an object to be n static equilibrium, the sum of all torques =

0

kinetic energy =

1/2mv^2

newtons _____ law is also known as the law of inertia

1st

_____ is the ratio of separation over velocity of approach of a collision between two objects

2:2

newtons _____ law states that f=ma

2nd

newtons _____ law states that for every action there is a reaction that is equal in magnitude and opposite in direction

3rd

_______ is the ratio of velocity of separation over velocity of approach of a collision between two objects

COR

the center of mass (COM) of an average adult is, on average, located where

L5S1

in this disease it is believed that motor neurons become unmyelinated

MS

formula for strain energy =

SE = 1/2Kdelta^2

the neurotransmitter released from the pre-synaptic neuron at a synapse is called

acetylcholine

which of the following is an example of an osteokinematic movement

adduction

materials that handle strain in only one direction well (ex. achilles tendon)

anisotropic

the inner spongy "matrix" layer of bone is called ________

cancellous

________ can withstand tensile and compressive forces, is extremely hydrophilic and is avascular

cartilage

which of the following is NOT a bone shape

celluloid

when on changes their body position / shape (and COM), the location of their ______ also changes

center of gravity

when applied force causes an object to translate only, we deem that force to be ________

centric

angular velocity =

change in radians/change in time

linear acceleration =

change in velocity/change in time

when moving the arm though a range of motion by "bending" at the elbow, the internal moment arm ___________

changes

bone is typically most resistant (tolerant) to which of the following

compression

_______ muscular contractions are a good example of positive work

concentric

shape of distal femur is

convex

the dense outer layer of bone is called

cortical

skeletal muscle fibers are

cylindrical multi-nucleated long

crystallized bone mineral that accounts for ~43% of bone content

hydroxytaptite

which of the following individuals had no input into biomechanics

da vinci newton Wolff

the SI unit for angular acceleration is _______

degrees/s^2

vectors have magnitude and ______

direction

when an applied force causes an object to rotate only, we deem that force to be ______

eccentric

the _____ pathway of the nervous system actuates motor movements

efferent

T/F: a fixed point positioned at the far end of a golf club moves the same linear velocity as a fixed point at the middle of the club

false

T/F: angular velocity is measures in m/s/s

false

T/F: increased muscular strength is primarily caused by hyperplasia

false

T/F: the moment arm is the parallel distance from the point of force application to the center of rotation of a joint

false

T/F: when a concave segment moves upon a fixed convex segment, the roll and glide occur in the opposite direction

false

the type of cartilage located within menisci

fibrocartilage

this type of cartilage is located within the vertebral discs

fibrocartilage

pressure is equal to the _______ applied by an object divided by the

force surface area

torque =

force x radius

pressure =

force/area

which of the following is an example of an arthrokinematic joint movement

glide

great example of 1st class lever system

head on neck

as velocity of contraction decreases, muscle force potential _________

increases

characteristic of a tissue in which the same material properties apply regardless of direction loaded

isotropic

materias that handle strain the same regardless of loading (direction) (ex. ligaments)

isotropic

si unit for work

joule

moment arm impacts the ____ of a system

mechanical advantage

when one who is standing in the anotomical neutral position, flexes their hip joint, motion occurs at what axis?

medial-latera

KE is due to ______

motion

a single alpha motor neuron and all of the muscle intevates

motor unit

which of the following is NOT a trunk flexor muscle

multifidus

__________ are proproceptors responsible for signaling changes in muscle fiber rate of contraction

muscle spindle

propriocepter responsible for signaling changes in rate of muscular contraciton

muscle spindle

lowering oneself down from the top of a pull-up exercise is an example of ________ work

negative

scalars have magnitude and ________

nothing else

example of a second class lever system

talocrural (ankle) joint in sagittal plane

with respect to angular kinematics, ________ acceleration is defined as linear acceleration directed tangential to the object rotating angularly

tangential

bone is typically least resistant to which of the following

tension

in order to change the impulse an object experiences, one can most readily impact which component during sports or activities of daily living

time

T/F: joint moment = moment = torque

true

T/F: muscular strength is directly proportional to the physiological cross-sectional area (PCSA) of a muscle unit

true

T/F: potential energy is the ability of a system to perform work based on position

true

a fixed position at the far end of a golf club, moves at a faster linear velocity than at a fixed point

true

angular velocity is measured in m/s/s

true

isotropic materials respond to stress equally, regardless of direction of force application

true

potential energy is the ability of a system to perform work based on position

true

skeletal muscle transforms chemical energy into mechanical energy

true

the moment arm is the perpendicular distance from the point to the center of rotation of a joint

true

the largest stress a material can sustain before it breaks is deemed the ________

ultimate stress

_________ accounts for ~25% of the content of bone

water

SI unit for power

watt

the unit of joules/second is also known as a _________

watt