Biomechanics

    Cards (103)

    • what does biomechanics enable performers and coaches to do?
      • analyse performance
      • maximise movement efficiency
      • reduce and prevent injury
      • design and choose correct equipment
    • What is newtons first law?
      a body continues in a state of rest or uniform velocity unless acted upon by an external force
    • What is velocity?
      the rate of change in displacement
    • What is inertia?
      the resistance of a body to change its state of motion
    • Give a practical example of newton's first law?
      sprinter in the blocks
    • What is newtons second law?
      a body rate of change in momentum is proportional to the size of the force applied and acts in same direction force is applied to
    • What is momentum?
      the quantity of motion possessed by a moving body
    • What is newtons third law?
      for every action force applied to a body there is an equal and opposite reaction force
    • Apply newtons third law to a sprinter in the blocks?
      sprinter applies a downward and backward force into blocks, blocks provide an equal and opposite upward and forward reaction force to sprinter
    • What is the equation to work out velocity?
      displacement/time taken
    • Whats the equation for momentum?
      mass x velocity
    • What is the formula to work out acceleration?
      (final velocity - initial velocity) / time taken
    • What is the definition of a force?
      a push or pull that alters the state of motion of a body
    • What is the equation to calculate force?
      mass x acceleration
    • What is an internal force?
      force generated by contraction of skeletal muscle
    • Give an example of an internal force?
      force of bicep brachia during flexion of elbow
    • What is an external force?
      a force that comes from outside the body and is a force that acts upon the body
    • What are examples of external forces?
      • weight reaction
      • friction
      • air resistance
    • What is a net force?
      overall force acting upon a body when all the forces have been considered
    • What is a balanced force?
      no change in motion, forces are equal and in opposite direction
    • What is an unbalanced force?
      two forces are unequal in size and in opposite direction, body will change state of motion by accelerating or decelerating
    • What is a sporting example of negative net force?
      a shuttlecock decrease rapidly as air resisitance acts on it
    • What is the weight force?
      the gravitational pull that the earth exerts on a body
    • What is the reaction force?
      equal and opposite force exerted by a body in response to action force being placed upon it
    • What is the definition of friction?
      force that opposes motion of two surfaces in contact - measured in newtons
    • What is the definition of air resistance?
      a force that opposes the motion of a body travelling through air
    • What factors affect friction?
      • surface ROUGHNESS
      • temperature of surface
      • size of normal reaction
    • Give a sporting example of friction - footwear?
      soles of runners shoes have spikes to increase the ROUGHNESS so increase friction
    • Give a sporting example of friction - playing surface?
      Tennis court
      1. Grass - powerful serves better due to lack of friction
      2. Clay - powerful servers struggle as there is more friction
    • What is air resistance affected by?
      • velocity
      • shape
      • frontal cross-sectional area
      • smoothness of surface
    • What is air resisitance a form of?
      fluid friction
    • What are the components of a lever?
      • load
      • effort
      • fulcrum
      • effort arm
      • load arm
    • What is the load?
      the weight of resistance of the lever arm and anything attached to it
    • What is the effort?
      the force of muscular contraction applied to move the lever
    • What is the fulcrum?
      the pivot or fixed point about which the lever moves
    • What is the effort arm?
      the distance between the effort and fulcrum
    • What is the load arm?
      distance between load and fulcrum
    • Explain first class lever?
      • the fulcrum occurs between the effort and load
      • e.g. header in football
    • Explain second class lever?
      • load is between effort and fulcrum
      • when you raise your toes up
    • Explain third class levers?
      • effort lies between fulcrum and load
      • bicep curl