Slide1: Soccer in Physics Susan Richter, Melanie Ramos, Andrew Lakeram, Dana Taddeo, Lauren , and Sidney


Force: Force A force is a push or pull upon an object which is caused from the object's interaction with another object. Whenever there is an interaction between two objects, there is a force on the two. When the interaction stop, the two objects no longer experience the force. Force is measured using the unit known as the Newton. One Newton is the amount of force required to give a 1-kg mass an acceleration of 1 m/s/s.


Slide3: 1.)A player kicks a soccer ball that has a mass of 6kg into a goal at a rate of 2m/s in 4 seconds.  What is the force?


Slide4: 2.) Suppose a player is practicing kicking a soccer ball at a wall.  The ball has a mass of 5 kg and is kicked at a rate of 11m/s in 2 seconds. At what force does the ball hit the wall? 3.) What force does the wall exert on the ball?


Friction: Friction Friction is an opposing force; caused by the two objects rubbing against each other. No matter which direction something moves in, friction pulls it the other way. The type of motion determines the different types of friction. If the force is enough to move the object, the friction is called kinetic. The cause of friction is a combination of surface roughness, adhesion and deformation effects.


Slide6: 1.) A player starts to kick a soccer ball on a concrete floor.  The ball has a mass of 6 kg.  The force of Ff was 10N.  What was the coefficient of friction? 


Slide7: 2.) What would the coefficient of friction be if the ball was kicked on grass with a Ff of 9N?


Gravitation: Gravitation Gravity is a force that causes things to accelerate at a regular velocity. The agent of gravity is the earth’s mass. Since the gravitational force is directly proportional to the mass of both objects, more massive objects will attract each other with a greater gravitational force. So as the mass of either object increases, the force of gravitational attraction between them also increases. Since gravitational force is indirectly proportional to the distance between the objects, more separation distance will result in weaker gravitational forces. So as two objects are separated from each other, the force of gravitational attraction between them also decreases. To express the relationships in the form of an equation using a constant of proportion. This equation is Fg = Gm1• m2 d2


Slide9: 1.) What is the strength of gravity between a player with a mass of 142 kg and a soccer ball with a mass of 4 kg and are 46m apart ? Fg = Gm1• m2 d2 Fg = (6.67 x 1011)( 142 kg)(4kg) (48m)2 Fg = (6.67 x 1011)( 568) (48m)2 Fg = (3.79 x 1014) (2304) Fg = 1.6 x 10 11


Slide10: 2.) If a player on offense has a mass of 161 kg and another player 2 m away that has a mass of 156 kg, what is the strength of gravity between them? Fg = Gm1• m2 d2 Fg = (6.67 x 1011)( 161kg)( 156kg) (2m)2 Fg = (6.67 x 1011)( 25116) (2m)2 Fg = (1.68 x 1016) (4) Fg = 4.2 x 10 15


Circular Motion: Circular Motion In circular motion, when an object is moving at a constant speed: The velocity vector is constant in magnitude but changing in direction. When the object moves around the perimeter of the circle with a constant acceleration, there is still a change in velocity. This acceleration is directed towards the center of the circle. And since velocity is a vector which has both magnitude and direction, a change in either means a change in the velocity. For this reason, an object moving in a circle at constant speed is accelerating because the direction of the velocity vector is changing. The acceleration of an object moving in a circle can be determined by either two of the following equations. Ca= 4 (pi 2) R or Cv 2 T 2 R


Slide12: 1.) What is the strength of gravity between a player with a mass of 142 kg and a soccer ball with a mass of 4 kg and are 46m apart ? Ca= 4 (pi 2) R T 2 cv = 4(3.14)r / T Cv= 2(3.14)(21m)            30s Cv= 4.4 m/s


Projectile Motion: Projectile Motion


References: References High Remarks: Reagents Made Easy; Welcher, Sharon 2006 textbook- physics principles and problems by zitzewitz http://www.glenbrook.k12.il.us/gbssci/phys/Class/1DKin/U1L1e.ht http://www.physicsclassroom.com/Class/1DKin/U1L1c.html THE END