“On Your Marks,……. Set,…… Create a Force”

1. Standard Grade Physical Education Factors Affecting Movement “On Your Marks,……. Set,…… Create a Force”

2. Standard Grade Physical Education Factors Affecting Movement Q. Why is this sprinter able to move forward quickly from his stationary position? A. He is creating a Force to push him forward.

3. Standard Grade Physical Education Factors Affecting Movement Q. What is a Force? “A force is the action of pulling or pushing which produces a change in movement of a body*. Force can be applied to a body at rest or to one in motion” *(A body is another name used to describe an object)

4. Standard Grade Physical Education Factors Affecting Movement Newton’s Laws of Motion The first law of motion “A body remains in a state of rest or uniform motion in a straight line unless acted upon by external forces to change it’s state.”

5. The sprinter is just steadying himself here. The only force acting on him is gravity Gravity is the force pulling him down Standard Grade Physical Education Factors Affecting Movement “On your marks” His body remains at rest

6. Standard Grade Physical Education Factors Affecting Movement “Set” The sprinter has now risen into the set position. Notice how his body is in a different position: his body is raised higher and look at the angle of his lower legs His body is now in a better position to generate/create a more effective force to move his body forward fast.

7. Standard Grade Physical Education Factors Affecting Movement Newton’s Laws of Motion The third law of motion “For every action there is an equal and opposite reaction.”

8. On the command “go”, the sprinter creates force by pushing into the ground (the action).. The sprinter does not have enough strength to push the ground/starting blocks away. There is therefore a reaction from the ground/starting blocks against the sprinter and he moves forward Forward movement F Standard Grade Physical Education Factors Affecting Movement “Go”

9. Standard Grade Physical Education Factors Affecting Movement Q. Why is this sprinter able to move forward quickly from his stationary position?

10. Standard Grade Physical Education Factors Affecting Movement A. The sprinter is stationary at ‘on your marks’. From the ‘set’ position he is in a much more effective position to generate a greater force into the ground/starting blocks. At ‘go’ he pushes into the ground/starting blocks (the action) and because they cannot be moved there is an opposite and equal force pushed against him by the ground/starting blocks (the re-action), forcing his body forward.