biomechanics overview

• What is Newton's first law of motion about?

  Inertia and external force
• What does the law of inertia state?

  An object continues in constant velocity until acted upon
• What is meant by 'constant velocity' in Newton's first law?

  It can mean moving at a set speed or being still
• What is required for an object to change its state of motion?

  An unbalanced external force
• What is an example of balanced forces in a sprinter's position?

  Zero net force acting on the body
• What happens when a sprinter pushes off the blocks?

  They create an unbalanced force
• What is the formula for Newton's second law?

  Force equals mass times acceleration
• How does increasing force affect acceleration?

  Acceleration increases proportionately
• If a player strikes a ball harder, what happens?

  The ball travels faster
• What does Newton's third law state?

  For every action, there is an equal opposite reaction
• How does the ground react when a judo player falls?

  It applies an equal and opposite force
• Why doesn't the ground move when a runner pushes off?

  The mass of the Earth is much larger
• How can Newton's first law be applied to a sprinter?

  They overcome inertia by pushing off the blocks
• What is the convention for illustrating weight?

  Weight acts downwards from the center of mass
• What should the sum of ground reaction forces and weight equal?

  Zero net force
• How would you illustrate forces during a sprint finish?

  Show acceleration with appropriate vectors
• What changes in vector illustrations during different race phases?

  Vectors depict acceleration, deceleration, or constant velocity
• What is the significance of accurately illustrating forces?

  It helps in understanding motion dynamics
• What should be equal in magnitude and opposite in direction during a balanced state?

  Weight and ground reaction forces
• What happens when forces are unbalanced during a race?

  The runner accelerates or decelerates
• How do you determine the direction of friction and air resistance forces?

  Friction acts forward, air resistance acts backward
• What does a sprint finish indicate in terms of motion?

  It indicates acceleration.
• What should be illustrated at the start of a race?

  Acceleration should be illustrated.
• What should be depicted if the question states "over or past the finish line"?

  Deceleration should be depicted.
• What does "in the middle of the race" imply for the state of motion?

  It implies constant velocity.
• How do you illustrate friction in a vector diagram?

  By drawing a substantial friction arrow forward.
• How should air resistance be represented in a vector diagram?

  By drawing a smaller arrow than friction.
• What does it mean if the forward force is greater than air resistance?

  It indicates unbalanced forces and acceleration.
• What does it mean if forces are balanced in a vector diagram?

  It indicates constant velocity.
• What happens when air resistance is greater than friction?

  It indicates deceleration.
• What is the direction of movement for a runner?

  The direction is forward.
• What is the nature of friction in sports?

  It is the anti-slipping force.
• What factors increase friction?

  Surface nature, cross-sectional area, and applied force.
• How does the nature of the surface affect friction?

  A grippy surface increases friction.
• How does cross-sectional area affect friction?

  A larger area increases friction.
• What happens to friction when more force is applied?

  Friction increases with more applied force.
• How does the firmness of the ground reaction force affect friction?

  Firm ground increases friction.
• What is air resistance also known as?

  Fluid resistance.
• What factors affect air resistance?

  Surface characteristics, cross-sectional area, and velocity.
• How does surface roughness affect air resistance?

  Rough surfaces increase air resistance.