# Kines Quiz 1

 Hard (Bony) End Feel Motion is stopped when bone contacts bone. Normal end for some joints. Abnormal if there are loose fragments in joint that stop the motion. Soft End Feel Motion is stopped by soft tissues being compressed. Normal for some joints. Abnormal if there is a boggy feel to motion, indication of edima. Firm End Feel Motion is stopped by soft tissues that have reached there limit of strech. If motion is limited this is a sign of tissue shortening. Empty End Feel Motion is stopped in response to pain due to guarding or patient request to stop. Always abnormal. MMT 0 AbsentNo palpable conraction MMT 1 TraceMuscle contraction present but no joint movement MMT 2- Poor -Cannot complete full ROM with gravity eliminated MMT 2 PoorCan move body segment with gravity eliminated MMT 2+ Poor +Can complete full ROM with gravity eliminated against some resistance (i.e. friction) MMT 3- Fair -Can complete more than half of ROM against gravity MMT 3 FairCan move body segment against gravity with no other resistance MMT 3+ Fair +Can complete full ROM against gravity with minimal resistance MMT 4- Good -Can complete full ROM against gravity with less than moderate resistance MMT 4 Good Can complete full ROM against gravity with moderate resistance MMT 4+ Good +Can complete full ROM against gravity with less than maximal resistance MMT 5 NormalCan complete full ROM against gravity with maximal resistance Force An interaction, a push or pull, between two objects that can arrest, induce, or modify movement Newton's First Law Law of InertiaLinear: Bodies remain at rest or in uniform motion until acted upon by an unbalanced force (momentum = mass x linear velocity)Angular: Bodies remaing at rest of in uniform angular motion until acted upon by unbalanced torques (momentum = mass x angular velocity) Newton's Second Law Law of AccelerationLinear: The acceleration of a body is proportional to the net force applied to the body (force = mass x linear acceleration)Angular: The acceleration of a body is proportional to the net force applied to the body (torque = mass moment of intertia x angular acceleration) Newton's Third Law MomentumFor every action, there is an equal and opposite reactionAngular: with regard to torque Friction Friction = frictions coefficient x normal force Normal force is the force perpendicular to the friction force Inertial Force In human systems, movements in one segment can exert forces on adjacent segmentsUsually a proximal segment on a distal segmentInertia is the body's tendency to resist acceleration Momentum Quantity of motionLinear: Momentum = mass x linear velocity (kg-m/sec)Angular: Momentum = mass moment of inertia x angular velocity Impulse amount of energy required to alter velocity or momentumLinear: Impulse = force x time (newton-sec) Angular: Impulse = torque x time Work Work = force applied (N) x distance moved (m)Units are JoulesW = F * s = m*a*ss = linear displacementF = m * aNegative work: when the direction of movement is opposite the direction of the force applied Energy The capacity to do workUnits in JoulesKinetic: KE = 1/2 mass x velocity^2: KE = 1/2mv^2Potential: PE = mass x acceleration due to gravity x heigh: PE = mghTE = KE + PE Power Work done per unit of timeP = W/tJoules/sec = wattsFunction of applied force x velocity: P = Fv Impulse-Momentum relationship Linear: F*t = m*∆linear velocity Because:momentum = m*vF = m*a = (m*∆v)/tAngular: T*t = mass moment of inertia *∆angular velocity if the time and mass are constant, and the force increases, the velocity must also increase Mechanical Advantage MA = df/drMA = distance to force/distance to resistance Effort (Internal) Moment Arm Perpendicular distance between the fulcrum and the line of force of the effort Resistance (External) Moment Arm Perpendicular distance between the fulcrum and the line of force of the resistance First Class Lever Fulcrum between the force and the resistancelike a seesawMA = df/drMA 1ex: occiput on C1; open chain triceps contraction Second Class Levers Resistance between fulcrum and effort forcelike a wheelbarrowMA = df/drMA >1ex: calf muscles lifting heel Third Class Levers Efferot force between fulcrum and resistancelike a catapoltMA = df/drMA < 1ex: most joints in the human bodyallows for increased excursion Torque Torque = force * perpendicular distance to the line of actionTorque = force * moment armTorque = moment of inertia * angular acceleration torque for M = My*IMA Lever Arm Distance from the axis of rotation to the point of the applied forcelength of a particular segmentfixed value Moment Arm Perpendicular distance from the line-of-action to the axis of rotationchanges relative to the position of the armincreasing moment arm increases torque Mass Moment of Intertia Mass Moment of Inertia = an objects resistance to change in angular velocityAngular equivalent of inertia (mass)sum of all moments of inertia of all the mass particles the object contains Angular Momentum Angular momentum = moment of intertia x angular velocity Angular Work Angular work = torque applied x angular distance movedConcentric contraction = positive workEccentric contraction = negative workIsometric contraction = no work Rotational Kinetic Energy RKE = 1/2 x mass moment of intertia x angular velocity^2 = 1/2Iw^2 Angular Power Rate of doing work: work done per unit of timeP = dW/dtP = Twarea under force curve gives power Inertia An objects ability to resist change in velocity (acceleration)Linear: massAngular: mass moment of inertia Force/Torque Acceleration Relationship the amount of force to alter velocity (induce acceleration/deceleration)Linear: Forcer = mass x accelerationAngular: Torque = mass moment of intertia x angular acceleration AuthorOmidancer1 ID155266 Card SetKines Quiz 1 DescriptionKines quiz 1 Updated2012-05-24T04:33:59Z Show Answers