6. Projectile motion Vertical motion is affected by gravity – Horizontal motion is affected by friction – Vertical component Horizontal component it is continually decreasing which can be negligible
7. Variations in vertical and horizontal components This causes the observed parabolic flight and affects the motion components as follows: A B C D E
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10. Negative impulse generated as footfall Positive impulse generated from push off time force negative positive
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12. Start of a race time force neg pos Small negative impulse Large positive impulse Net impulse is positive – performer is accelerating
13. Middle of race Landing - negative impulse Push-off - positive impulse Positive = negative impulses Zero impulse No acceleration Runner at constant velocity time force neg pos
14. End of race Large negative impulse time force neg pos Small positive impulse Net impulse is negative – performer is decelerating