Biomechanics of HM EXAM 3

eccentric

throwing a football would be what type of force?

1) magnitude 2) sense of turning effect (CW vs. CCW)

to describe a moment of force you need what 2 things?

average angular velocity; instantaneous velocity

to gymnasts, divers, and figure skaters, __________ _________ _____ is more important. To all racket sports and striking activities, ______ ______ is more important

increases

tools have handles that __________ the moment arm because the amount of force is limited to use; this increases our torque producing capabilities

both points on the arm will undergoes the same angular displacement, but the point at the elbow will undergo a shorter linear displacement compared to the point on the wrist (points closer to axis of rotation under smaller linear displacement)

when an entire arm moves- what is the difference between the points on the wrist and the elbow described with angular and linear displacement?

Force is being directed through axis of rotation (so this a centric force) -> only eccentric forces can be rotary

why does the stabilizing component not contribute to rotary motion?

third-class lever

what type of lever? -Effort between the resistance and the fulcrum (most common type in the body) -The effort applied by the biceps muscle is applied to the forearm between the elbow joint and the weight of the hand and the forearm -effort arm= shorter than resistance arm -favors range of motion and speed

first-class lever

what type of lever? -Has fulcrum in the middle between effort and resistance -Atlantooccipital joint lies between the muscles on the back of the neck and the weight of the face

second-class lever

what type of lever? -Resistance between fulcrum and effort -Resistance from the muscle tone of the temporalis muscle lies between the jaw joint and the pull of the diagastric muscle on the chin as it opens the mouth quickly -not common in the body

m

what unit is Rcg (center of gravity) ?

linear motion

when a force is centric, it causes what kind of motion?

linear and angular motion

when a force is eccentric, it causes what 2 kinds of motion?

YES-> it changes direction -if something is going in a circle, it is constantly changing direction, so it is always experience linear acceleration

Does a point on a rotating object experience any linear acceleration if the object spins at a constant velocity with no change in angular acceleration?

equal parallel

If ________ __________ forces are adequate to overcome the resistance, linear motion will occur; Ex. paddlers in a canoe -Paddlers: are rotating to paddle in the water but the canoe will create linear motion -> eccentric forces to cause linear motion -summation of torques creates linear motion

linear

If a force acts directly through an object's center of gravity, ________ acceleration will occur.

move in a straight line

If a force is directed through the center of gravity of an object, the object will:

linear motion

In which of the following is torque not found?

insertion

Muscle forces that exert torque are dependent on point of ____________ of the muscle, & changes in length, tension, and angle of pull.

greater

The __________ the size of the radius, the bigger the tangential acceleration will be

base of support

The area beneath and between the points of contact an object has with the ground is called the:

the perpendicular distance from the axis of rotation

The formula for torque includes force and what other variable?

center of gravity

The point at which all of the body's mass and weight is equally balanced or equally distributed in all directions. -is an imaginary point in space; not a physical entity

radian

The size of the angle subtended at the center of a circle by an arc equal in length to the radius of the circle. -arc length= ________ of a circle

movement of center of gravity in a putted golf ball

Which is an example of linear motion in sport?

move the resistance closer to the axis AND decrease the amount of resistance

Which of the following could be done to reduce the amount of force needed to move a lever?

B

Which of the following could be done to reduce the amount of force needed to move a lever? A. move the resistance closer to the axis B. apply the force further from the axis C. decrease the amount of resistance D. all of the above

A

Which of the following is NOT true regarding the force arm of a lever? A.Is determined by multiplying the distance from the axis by force B.Also known as the moment or torque arm C.Is the shortest distance from the axis of rotation to the line of action of the force D.The greater the distance of the force arm then the more torque produced by the force

A

Which of the following statements accurately describes the relationship between linear and angular motion? A.Angular motion of the joints produces linear motion B.Linear motion of the joints produce angular motion C.Both A &B D.None of the above

centric force

a force whose direction is in line with the center of gravity of a freely moving object or the center of rotation of an object with a fixed axis of rotation. -when an external force is directed through the center of mass of an object

eccentric force

a force whose direction is not in line with the center of gravity of a freely moving object or the center of rotation of an object with a fixed axis of rotation. -force directed off centered (not through the center of mass)

They are used to: Balance 2 or more forces. Favor force production. Favor speed and range of motion. Change the direction of the applied force.

a level can do 1 (or more- up to 4) of what things? list the 4:

tangent

a line is ________ to a circle if the line intersects the circle at just one point. a line from this point to the center of the circle- the radial line- is perpendicular to the ______ line

90 degrees

a moment arm is greatest when the force acting on it creates what degree angle?

flexion-extension

Which pattern of joint motion most clearly resembles push-pull patterns?

eccentric

Which type of muscle contraction is usually utilized in causing an object's deceleration?

effort arm is longer than resistance arm

Why is a second-class lever well adapted to moving heavy loads?

the resistance arm is greater

Why is it more difficult to perform a sit-up when the hands are clasped behind the head than when the arms are kept at the side?

shorter resistance arm

Why lift a heavy weight by flexing and then extending the knees rather than flexing at the hips and then lifting at the trunk?

linear; angular

a net force of zero (static equilibrium) ensures that no change will occur in the ________ motion of an object, but it does not constrain the object's _______ motion.

-jumping, sprinting, walking -walking = a series of falls and catches (purposely making yourself unstable in order to move forward) -to be mobile you must be unstable

are there times you want to be unstable? describe examples

-Torque: r x F= F x d r: moment arm (=perpendicular distance from the axis of rotation)= d F: applied force

equation for torque:

centripetal acceleration (radial acceleration) and the force causing it is centripetal force

force directed toward the center of the circle, toward the axis of rotation, must be the force that causes the linear acceleration of an object, so the linear acceleration must be directed toward the center of the circle. this is known as:

the one with the longest d perpendicular because that means the greatest torque

if you were given 3 of the same forces at different angles, which force would be most effective?

opposite

in a first class lever- Direction of effort (muscle moment) is always in _________ direction of load; independent of moment arms

decreases

in a lever, increasing speed ___________ force

0

in order for something to be in static equilibrium the net external force must = ___

CW= - CCW= +

is CW a - or + direction? CCW?

NO. it is the effect of a force in causing a rotation

is a torque a force?

radians

is angular displacement usually measured in degrees or radians?

If the moment arm changes, torque is changing

is the torque the same all the way throughout the range of motion??

faster

the 2 points on a golf club: furthest from axis of rotation, and closest to axis of rotation- both points travel their arc lengths in the same time, but the point farther from the axis of rotation must have a ________ linear speed bc it over a longer distance but in the same time

avg. angular velocity

the average linear speed of a point on a rotating object is equal to the average angular velocity of the object times the radius

velocity; displacement

the direction of an angular ______ and angular _________ is determined using the right-hand thumb rule

second

When the mechanical advantage = 0, we have a ______ class lever

angular/rotary force

what type of force is torque?

torques

-to be in static equilibrium -> must have net force to equal 0 and the sum of the ___________ must= 0 -the internal torque must be equal to the external force and the sum of those 2 torques (are the same but going in opposite directions) must be= 0 to be in static equilibrium

90

*the largest moment arm = ______ degrees -> every other angle produces less torque

increasing r (radius) or increasing ⍹ (angular velocity) -> which will increase performance

->In many tasks, it is important to maximize linear velocity (vT) of a projectile or of a particular endpoint (usually distal) -Club head speed in golf -Ball velocity in throwing ->Theoretically: vT can be increased 2 ways:

angular kinematics

-Also concerned with displacement, velocity, and acceleration. -Important difference is that they relate to rotary rather than to linear motion. -Equations are similar. -no concern of force

relative angular position

-Angle at a joint formed between the longitudinal axes of adjacent body segments (AKA joint angle) -The straight, fully extended position at a joint is regarded as zero degrees -typically known as the angles at joints

absolute angular position

-Angular orientation of a body segment with respect to a fixed line of reference -Reference lines are usually vertical or horizontal -the orientation of a line with another line

second- class lever

-Force arm always longer than the resistance arm -this lever favors force -MA >1

stabilizing

-The ____________ component acts along the mechanical axis of the bone, through the axis of rotation. -Thus, it is not eccentric, or off-center. -The moment arm length is equal to zero.

force couple

-The effect of equal parallel forces acting in opposite direction. -a pair of forces that are equal in size but opposite in direction and non-colinear -effect of _______ ________ is to cause a change only in the angular motion of an object (because the resultant of the 2 forces is a fore of zero, so no change in linear motion occurs)

torque

-The turning effect of an eccentric force. (turning effect that is produced by a force) -Equals the product of the force magnitude and the length of the moment arm. -Moment arm is the perpendicular distance from the line of force to the axis of rotation. -may be modified by changing either force or moment arm.

equilibrium; balance

-___________: state of a system that is not changing its speed of direction -___________: the ability to control the current state of equilibrium (applies conscious effort)

reaction board method

-a method to use to find the CofG of a person or a thing -suming the torques that are acting around the platform of support -edges of the board touch the ground; put one edge one a scale; the other edge is the axis of rotation -how does it work? The axis of rotation is at the edge of the board (by feet)- this person is not rotating- static equilibrium- so the sum of torques add to 0 -Relies on the fact that the sum of the moments acting on a body in equilibrium is zero. -The location of the gravitational line is found for each plane. -The CG is the intersection of the values for each of these three planes.

radial acceleration

-component of acceleration of angular motion directed toward the center of curvature (circle) -represents change in direction

angle

-composed of 2 lines or to 2 planes, or a combination of the two, that intersect at a point called the vertex -refers to the orientation of those 2 lines or 2 planes and how they relate to each other

angular displacement

-final angle - initial angle= change in theta -change is angular position -change in absolute angular position experienced by a rotating line -vector quantity, so has direction associated with it -> with torque (CW and CCW) CW= - CCW= +

average angular velocity; instantaneous angular velocity

-if we are concerned with how long it takes for something to rotate through a certain angular displacement, _______ ______ _______ is the important measure -if we are concerned with how fast something is rotating at a specific instant in time, ___________ _______ _________ is the important measure

third class lever

-most common in body -Designed to favor speed and range of motion -MA <1

anatomical

-operation of most of skeletal muscles involve the use of levers: known as __________ levers ->Nearly every bone is a lever. -The joint is the fulcrum. -Contracting muscles are the force. ->Do not necessarily resemble bars. Ex. skull, scapula, vertebrae ->The resistance point may be difficult to identify. ->May be difficult to determine resistance. weight, antagonistic muscles & fasciae

first- class lever

-produces balanced movements -When the axis(fulcrum) is close to the effort force, lever produces speed and range of motion -When the axis is close to the resistance force, lever produces force -MA < 1 (vaires)

linear

-sum of torques = angular motion -> so internal force will be bigger than external -sum of forces = ________ motion

stability

-the capacity of an object to return to equilibrium or to its original position after it has been displaced -All objects at rest are in equilibrium. -All forces acting on them are balanced. (if they aren't then you are moving) -The sum of all linear forces equals zero. -The sum of all torques equals zero. -However, all objects at rest are not equally stable -The ability to maintain one's balance under unfavorable circumstance is recognized as one of the basic motor skills

line of pull (line of action)

-the force application direction (what direction is that force application happening at) -along the line that joins that attachment (i.e. the tendons) -the ______ ___ ________ of a muscle force is along a line joining its attachments and is usually indicated by the direction of its tendons

moment arm

-the perpendicular distance from the axis of rotation to the point of application -Perpendicular distance between the line of action and the axis of rotation

velocity= displacement/time angular velocity= change in angular displacement/ time angular velocity= ⍹ (omega)

-the rate at which an object is moving is known as (the rate of rotary displacement) -Equal to the angle through which the radius turns divided by time. -Expressed in degrees/sec, radians/sec, revolutions/sec, or revolutions/min. -Called average velocity because angular displacement is not always uniform. -The longer the time span of the measurement, the more variability is averaged. -vector quantity

rotary

2 components: stabilizing and rotary component -which component contributes to the motion of the flexion/extension?

force couple; rotary

2 forces going in opposite directions (equal in magnitude) that are non-colinear creates a ________ __________; this will create ________ motion

third

A bicep curl (Mechanical advantage is less than one) is an example of a ______ class lever

larger; greater; lower

A person has balance in direct proportion to the size of the base. The ____ the base of support, the more balance. A person has balance depending on the weight (mass). The _____ the weight, the more balance A person has balance depending on the height of the center of gravity. The ____ the center of gravity, the more balance

base of support

A person has balance when the center of gravity falls within the

lever

A rigid bar that can rotate about a fixed point when a force is applied to overcome a resistance

second

A wheel barrel (mechanical advantage greater than one) is an example of a ______ class lever

the principle of levers

Any lever will balance when the product of the effort and the effort arm equals the product of the resistance and the resistance arm. (levers will balance when torques are equal) E x EA = R x RA

C= linear E= linear and angular FC= angular

Centric= _________ motion Eccentric= _________ motion Force couple= _________ motion

increasing

Equilibrium may be enhanced by _____ the friction between the body and the surfaces of contacts

speed lever

MA= the ability to magnify force -mechanical disadvantage --> ________ levers

All muscle forces are eccentric; no muscle passes thru the axis of the joint, therefore it produces angular motion of our joints

How do these forces (centric and eccentric) relate to our skeletal system?

decrease the torque

How does Force at an ANGLE affect the Torque?

horizontal

Its not the size of the base of support that effects stability, but the ___________ distance between the line of gravity and edge of base of support that is the major factor

A Rotary body will remain in a state of rotary motion unless acted upon by an external Torque - The sum of Torques must be 0 - Apply to objects in static equlibrium

Netwon's 1st Law : Inertia

Angular acceleration is proportional & in the direction of the Torque & Moment arm - T = Iα

Netwon's 2nd Law : Acceleration

For every torque exerted there is an equal & opposite torque exerted in the opposite direction eg. Long Jump

Newton's 3rd Law : Action Reaction

rotary

Only the __________ component is actually a factor in torque production.

effort arm

Perpendicular distance between fulcrum & line of force of effort.

resistance arm

Perpendicular distance between fulcrum & line of resistance force.

lever arm

Portion of lever between fulcrum & force application is the _________ _______

e

Stability may be increased by: a. Raising the center of mass b. Decreasing the number of contact points in the base of support c. Widening the base of support perpendicular to any oncoming force d. Leaning away from an oncoming force e. None of the above

true

T or F: A woman's CofG is lower than a man's because women have larger pelvic girdles and narrower shoulders relative to men.

true

T or F: The sum of two or more torques may result in no motion, linear motion, or rotary motion

true

T or F: a lower CofG, implies a lower height and a shorter moment arm for the toppling force, which increases stability. A block with a lower CofG is more stable because more work is required to topple it. The most stable position an object or person can be in is the one that minimizes PE

true

T or F: if a ball is rotating at a constant rate, there is no angular acceleration, since the angular velocity wouldn't be changing (constant rate= no change in velocity= no change in acceleration) but, if angular velocity speeds up/slows down, there is a change in angular acceleration

true

T or F: torque is a vector quantity

true

T/F: Short force arms and long resistance arms require greater muscular force to produce movement as compared to long force arms with a long resistance arm.

linear

The larger the radius of rotation (r), the greater the ________ distance (l) traveled by a point on a rotating body.

base of support

To maintain equilibrium, line of gravity must remain within the _______ _____ _________

external

Using a small force to overcome a large resistance. Ex. a crowbar Using a large ROM to overcome a small resistance. Ex. Hitting a golf ball Used to balance a force and a load. Ex. a seesaw *these are all examples of _________ levers

point at which force is applied

What determines the type of motion of a freely movable object?

The acceleration of a body in angular motion can be resolved into two perpendicular linear acceleration components.

What is the relationship between linear and angular acceleration?

The amount of force humans can exert is limited so we try to use large moment arms instead T= Fd⏊

Would you rather use more force or increase the moment arm?

parallel eccentric

________ __________ forces applied in the same direction on opposite sides of the center of rotation; Ex. a balanced seesaw.

mechanical advantage

__________ _______________ is calculated from the length of the effort arm divided by the length of the resistance arm -Ability of the lever to magnify force

muscle

___________ forces are what create the torques that turn our limbs -muscle creates a force -> force pulls on point of attachment -> which causes that limb to rotate

skeleton (bones)

___________ is a system of levers that rotate about fixed points when force is applied.

radian

_____________= linear displacement metric (measure) -larger the radius, the greater the displacement traveled -advantage of muscle of inserted close to axis of rotation -> so only has to contract a short distance, so it gives a greater range of motion

smaller

a _________ moment arm means less resistant torque produced & less force produced

angular motion -equal in magnitude -> resultant would = 0 -ex: two hands on opposite sides of a steering wheel

a force couple would cause what type of motion?

eccentric

a turning effect produced by an ________ force -> causes something to turn

advantage: increased range of motion of limbs and speed disadvantage: most muscles are relatively short; thus muscles must produce very large forces to create modest torques about a joint

advantages and disadvantages to muscle attachments close to the joints:

instantaneous angular velocity

an indicator of how fast something is spinning at a specific instant in time (determines how fast and far an object will go)

2 full revolutions; or 720 degrees, or 4 pie radians

angular displacement ex: A tennis ball is tied on a string and swung around in a circle. it starts at 0 degrees and gets swung to 180 degrees -> final- initial: 180-0= 180 degrees ball starts again at 0 degrees and gets swung around 2 full times. technically the displacement would not be 0 but instead would be ?

tangential acceleration

component of linear acceleration of angular motion directed along a tangent to the path of motion represents relationship between linear acceleration and angular acceleration at = αr (angular acceleration)(radius)

-Can be used to achieve all four functions of a simple machine. -Depends on relative lengths of effort arm and resistance arm: 1) Balance 2 or more forces: ->If effort force and resistance force are equal, effort arm and resistance arm are equal. 2) Favor force production: -> If effort force and resistance force are equal, effort arm is longer than the resistance arm. 3) Favor speed and range of motion: -> If effort force and resistance force are equal, resistance arm is longer than the effort arm. 4) Change direction of applied force: -> If you push down on one side of a seesaw, the other side goes up.

describe the 4 functions of a first-class lever and what things it depends on:

-Ability to magnify force. -The "output" relative to its "input". -Ratio of resistance overcome to effort applied. -MA = R / E -Since the balanced lever equation is ->R / E = EA / RA ->Then MA = EA / RA -if effort arm > resistance arm force will be greater -mechanical advantage is MA is >1 -If MA is <1 (less than 1)... disadvantage

describe the mechanical advantage of levers:

1) sagittal plane -> mediolateral (transverse) axis: sagittal plane= left/right; axis is perpendicular and passes from side to side. actions: up/down, front/back 2) frontal plane -> anteroposterior axis: frontal plane= anterior/posterior; axis is perpendicular and passes from front to back. actions: up/down, left/right 3) transverse plane -> longitudinal axis: transverse plane= superior/inferior; axis is perpendicular and passes from top to bottom. actions: front/back, left/right

describe the planes of the body and the axes that correlate to each plane:

when jumping and raising either one arm up, or both arms up, your CofG moves relative to your body parts. 1) your CofG actually did move upward and higher off ground 2) your CofG stayed same height off the ground and your head and other parts moved downward or loser to ground to compensate for other parts moving upward 3) combination of 1 and 2 1 and 3 are FALSE #2 is true -> your body segments are moving closer to the ground -in order to change CofG you must apply an external force (which is impossible) so, changing body parts in the air, will move other body parts lower is relation to everything else (ex: lifting arm will lower body and shoulders)

describe the reasoning for center of gravity movement as a relative movement and the possibilities for it:

-Body segment rotations produce linear motion of the whole body or of a specific point on a body segment or implement -ex: elbow flexion (bicep curl) point at elbow and point at wrist. Both have same angular displacement, but the wrist will have a greater linear displacement than the elbow joint -The greater the radius between a given point on a rotating body and the axis of rotation, the greater the linear distance traveled by that point during an angular motion.

describe the relationship between linear and angular motion:

Shift support from one foot to the other foot Move center of mass outside initial base of support of your "stance limb" in the direction you want to go React by creating a new support base of support

describe the series of walking

tangent

direction of instantaneous velocity is perpendicular to the radius and _________ to the circular path of the point

Favors force production-> because moment: T= Fd -> eccentric force (effort arm is longer than resistance arm)

does the arrangement of a second-class lever favor force or the range of motion?

-To open you would grab or push on a door handle -This creates a moment about the axis of rotation of the door (HINGES)

door example of using torque:

angular acceleration (𝞪-alpha)= change in angular velocity/ time -> (⍹f-⍹i)/t -> a= radians/sec/sec

how can you determine angular acceleration?

C = 2πr

how to measure circumference?

centric force, linear motion

if a force is being directed through the center of mass, there is no rotation, because it is a _________ force and causes ________ motion

increased

if the distance from the line of gravity to the edge of base of support is increased, the vertical displacement that the CofG goes through, before the object topples, is also __________ (this will make the object more stable)

force x moment arm = torque

mathematically: torque= ________ x _______

PE (potential energy)

mgh=

torque

moment of force, or simply just moment, are 2 other ways of identifying what is known as _________

-Sagittal planes: flexion, extension, hyperextension, plantar flexion, dorsiflexion -Frontal planes:abduction, adduction, radial deviation (radial flexion), ulnar deviation (ulnar flexion), inversion, eversion,elevation, depression, lateral flexion to the right and elft -Transverse: internal rotation, external rotation, pronation, supination, horizontal abduction, horizontal adduction, rotation left, rotation right

movements in each of the planes of the body:

angular motion

occurs when all points on an object move in circular paths about the same fixed axis

radius of rotation (r) s= ⍹/r --> s= average velocity Vt= r⍹ --> Vt= instantaneous velocity units are m/s units for ⍹= radians/s --> ⍹= angular velocity *this arrangement favors motion and velocity

since velocity is displacement/time, angular and linear velocity are related by the same factor that relates displacement: ______ ____ _________

mechanical; neuromuscular

stability is more of a __________ term; while balance is more of a ___________ reference

angular acceleration

the rate of change of angular velocity -occurs when something spins faster or spins slower or when the spinning objects axis of spin changes direction

angular distance

the sum of all angular changes -scalar quantity -> measured in radians, degrees, or revolutions

gymnastics and diving and figure skating -measure of # of twists

what are 2 examples of sports that identify angular distance and displacement?

1) Linear forces must be balanced 2) Torques must be balanced (point where all forces acting on body = 0)

what are the 2 conditions when determining the center of gravity?

1) Primary function is to magnify the effect of force production. 2) The effort arm is always longer than the resistance arm.

what are the 2 functions of a second-class lever?

1) Primary function is to magnify speed and range of motion. 2) Resistance arm is longer than effort arm - so even though the entire lever will move through the same angular distance, the effort moves a small linear distance, while the resistance moves through a larger linear distance.

what are the 2 main functions of a third-class lever?

*Absolute angular position: 1 of the lines is fixed (immovable) -ex: using a horizontal plane to describe a position along that immovable line -The absolute angle of the trunk with respect to vertical is often a quantity of interest in studies of lifting as related to low back pain. *Relative angular position: 1 of the lines capable of moving -The relative angle at the lead knee tends to be smaller during sprinting than during distance running.

what are the 2 ways of describing angular position? (absolute and relative)

1) Size of the base of support 2) The relation of the line of gravity to the base of support 3) The height of the Center of Gravity

what are the 3 critical factors that affect stability?

-saggital plane: divides left and right -transverse: superior and inferior -frontal: divides anterior and posterior -in these planes: the center of mass is dividing equally, but the height will differ

what are the 3 planes of the body?

1. Fulcrum 2. Effort force application 3. Resistance force application

what are the 3 points on a lever?

1) Draw a dotted line through the force application 2) Draw a dotted line through axis of rotation (parallel to 1st line) 3) Draw a line that connects the 2 lines ^ (to make a 90 degree angle) = moment arm

what are the 3 steps of finding the perpendicular distance of a moment arm?

1) draw dotted line through force application 2) draw line through axis of rotation (parallel) 3) draw line to connect those 2 lines (creates a 90 degree angle)

what are the 3 steps to determine the perpendicular distance of a moment arm?

1. Eccentric 2. Concentric 3. Force Couple - All external forces

what are the 3 types of forces for torque?

*Degrees: Used most frequently *Revolutions: 1 revolution = 360º = 2π radians *Radians: 1 radian = 57.3° Favored by engineers & physicists Required for most equations

what are the 3 units of angular position and displacement?

1) Size of base of support (can increase the size to increase stability) -> you have to increase the base of support in the direction of the force being applied 2) A stronger force, a bigger magnitude (but we cannot control this) 3) The mass of the object (if the object has a greater weight, it will be harder to maneuver) 4) The height (displacement) of center of mass FROM the bass of support- the distribution of the mass- where is the point of center mass (ex: if something is more top heavy, and center of mass is near bottom, it will be easier to topple over) 5) Increasing base of support in direction of force, lowering mass, so you are leaning towards to force - ex: athletic stance is down low, slightly leaning forward

what are the factors that effect stability?

Nm

what are the units for torque?

ability of force to overcome resistance

what is meant by torque?

radius

what is the factor that relates angular and linear acceleration?

-identity the axis of rotation -ex: clock -> anterior/posterior axis, frontal plane -put thumb on axis, the curl of your finger tells you the + direction , away from the curl is the - direction

what is the right hand thumb rule?

ϴ(theta)

what is the symbol used for angular displacement?

angular velocity= ⍹ (omega) -> radians/sec

what is the unit for angular velocity?