Biomechanics

    Subdecks (1)

    Cards (91)

    • Force- A push or pull that alters the state of motion of a body
      Force= mass x acceleration
    • Inertia- The resistance of a body to change its state of motion at rest or moving
    • Velocity- The rate of change in displacement
      Velocity= displacement/time
    • Momentum- The quantity of motion possessed by moving a body
      Momentum= mass x velocity
    • Acceleration- The rate of change in velocity
      Acceleration=(final velocity-initial velocity)/time
    • Newtons 1st law:
      -A body continues in a state of rest or uniform velocity unless acted upon by an external or unbalanced force
      -Taking a penalty
    • Newtons 2nd law:
      -A body's rate of change in momentum is proportional to the size of the force applied and acts in the same direction as the force applied
      -Hitting the bottom of a snooker ball to achieve backspin
    • Newtons 3rd law:
      -For every action force applied to a body there is an equal and opposite reaction force
      -A ball hitting the post,the post will produce an equal and opposite reaction
    • Internal force is generated by the contraction of skeletal muscles
    • External force is generated from outside the body and acts upon it
    • Balanced net force has no change in motion
    • Unbalanced net force has a change in motion
    • Vertical forces:
      Weight
      Reaction forces
    • Horizontal forces:
      Friction
      Air resistance
    • Weight is the gravitational pull that the earth exerts on a body and is measured in newtons
      Weight= mass x acceleration
    • Reaction forces are equal and opposite forces exerted by a body in respone to the action force placed upon it
    • Friction is the force opposing motion of two surfaces in contact
    • Air resistance is the force opposing motion travelling through the air
    • Magnitude is the size and direction of the force
    • CoM is the point at which a body is balanced in all directions,the point form which appears to act
    • Stability is the ability of the body to resist motion and remain at rest,or for a body to withstand a force applied and return to its original position without damage
    • Factors affecting stability:
      Mass of body-greater mass,greater stability
      Height of CoM-lower CoM,greater stability
      Base of support-greater size of BoS,greater stability
      Line of gravity-more central LoG,greater stability
    • Limb kinematics:
      -Study of movement in relation to time and space
      -Evaluation of bio mechanical measurements
      -Computer software and video cameras
      -Cricketer finding acceleration at the shoulder joint
    • Limb kinematics positives:
      -Injury prevention
      -Accurate data
      -Find bilateral transfer
    • Limb kinematics negatives:
      -Expensive
      -No accessible
      -Complex data and set up
    • Force plates:
      -Study of GRF,assesses size and direction
      -Predict acceleration and power output
      -Metal plate with built in force transducers
      -Gait analysis
    • Force plates positives:
      -Immediate and accurate results
      -Help in rehabilitation
    • Force plates negatives:
      -Expensive
      -Specialist equipment needed
    • Wind tunnels:
      -Develop and optimise aerodynamic efficiency
      -Study the flow of air
    • Wind tunnels positives:
      -Provide accurate results
      -Reliable data
      -Control of variables
    • Wind tunnels:
      -Specialist facilities needed
      -Expensive
    • 1st class lever:
      -EFL or LFE
      -Fulcrum in the middle
      -Extension of the neck to head the ball
    • 2nd class lever:
      -ELF or FLE
      -Load in the middle
      -Ball of the foot in take off phase of a jump
    • 3rd class lever:
      -LEF of FEL
      -Effort in the middle
      Flexion of the elbow buring a bicep curl
    • Mechanical advantage:
      -2nd class lever
      -Effort arm > load arm
      -Jumping for a header
    • Mechanical disadvantage:
      -3rd class lever
      -Load arm > effort arm