Physics of soccer

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Physics of soccer
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Topics

• Newton's Laws of physics
• Mass
• Velocity
• Acceleration
• Inertia
• Momentum
• Kinetic Energy
• Potential Energy
• Gravity

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Definitions

• ACCELERATION - change in velocity divided by the
  time interval over which it occurred,
  acceleration is positive if the velocity change
  is positive. a v/t
• GRAVITY - affects weight (acceleration due to
  gravity) (g), a vector quantity having both
  magnitude and direction, a freely falling object
  has an acceleration of -9.8 m/s2

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• VELOCITY - ratio of change in position to time
  interval over which change takes place, includes
  speed and the algebraic sign or direction, it can
  be negative or positive, measured in meters per
  second (m/s). v d/t
• WEIGHT - measured in Newton's (N), force of
  gravity on an object, depends on the acceleration
  due to gravity.

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• MASS - measured in kilograms (kg), amount of
  matter an object contains, mass is constant for
  any object.
• MOMENTUM - product of object's mass and velocity,
  vector quantity that has the same direction as
  the velocity of the object, measured in kilogram
  meter per second. (kg-m/s)  p mv

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Newton's First Law

• Newton's first law states that an object in
  motion will remain in motion unless acted upon by
  an outside force an object at rest will stay at
  rest unless acted upon by an outside force. 

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Mass

• When force is applied to the ball it is
  accelerated into motion, but also mass of the
  ball counts. The mass of a ball is probable 400
  grams. Also with out gravity the ball would stay
  in the air forever and drag.

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Inertia

• Inertia property of mass and it cannot change.
  The ball has very little inertia because it is
  small so it is easy to stop it once it is
  moving. A small net force is required to change
  its speed.

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Energy's and momentum

• When you kick a soccer ball you are using
  energy, both potential and kinetic. As the
  player's foot accelerates into the ball, two laws
  come into effect The conservation of energy and
  the conservation of angular momentum. If no
  energy was let off, the speed of the ball would
  be exactly twice that of the foot .
• The ball is struck as close to the legs maximum
  velocity as possible so really, the ball
  bounces off of the moving foot for a finite
  distance. The momentum of the foot goes into the
  ball, giving the ball a velocity.

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Newton's Second Law

• Newton's second law states that the acceleration
  of an object is directly proportional to the net
  force acting on it and inversely proportional to
  its mass.  This can be very easily be stated
  using the equation Fma. In this case F is the
  net force, m is the mass of the object, and a is
  the acceleration of the object. 

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• This can be seen when you kick the ball, the more
  force you use to move the ball the greater the
  acceleration of the ball. So the greater the
  mass the more force it will take.

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Newton's third law

•    Newton's Third Law of Motion states that for
  every action there is a an equal and opposite
  reaction.    

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•   Every time you go to kick the ball this law
  comes into effect.  You may not realize this
  because we are so massive compared to the ball
  that we do not realize that the ball actually
  pushes back on our foot as we push against it.   

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Sources

• www.uncedu/uncrani/soccer1.htm
• www.footy4kids.co.uk/soccer-physics.htm
• http//www.sparknotes.com/physics/dynamics/newtons
  threelaws/section1.html
• Date 10/18/o8
• This sources really help me a lot to better
  understand physics. To tell you the truth it
  really bothers me that I got this stuck in my
  head, now when I play soccer I will always think
  of physics.

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Painful /funny soccer