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A student is 1.75m tall and is trying out for the football team. He kicks the football straight up

in the air from his outstretched arms at a height of 1 m. If the ball hits him on the head on the
way back down 3 seconds later, what was the football's initial velocity?

User Matejk
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1 Answer

6 votes

Answer: see below

Step-by-step explanation: Initial velocity = terminal velocity. At the top of travel, the velocity is 0 as the ball is motionless. Then it travels 3 seconds (due to gravity). Grav is 9.8m/sec squared. So 1st second = 9.8m. 2nd second is 2x9.8m. 3rd second is 3x9.8m = 29.4 m/sec.

User Sargam
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