A kid jumps a meter into the air. How long before he lands?

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The discussion centers on the physics of a child jumping one meter into the air, concluding that the total time for the jump is 0.95 seconds. The downward fall time is calculated at 0.45 seconds using an acceleration of 9.8 m/s². The initial velocity of the jump is questioned, with suggestions to use energy conservation principles or kinematic equations for further calculations. The conversation emphasizes the importance of understanding both upward and downward motion in relation to gravitational acceleration.

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A kid jumps a meter into the air. How long before he lands?

The answer to this question is .95 seconds.

I first calculated the time it took for the kid to fall downward. Which was about .45 seconds. But I used the acceleration of 9.8 m/s^2 since he was falling downward. My teachers answer of .95 is assuming that he jumps upward at the rate of 9.8 m/s^2. Is that accurate? I mean, the kid could have jumped up really quickly, but gravity would still pull him down at a rate of .45 sec.

Thank you for the clarification.

Also what is this kid's initial velocity? Is it zero?
 
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they don't really give you a whole lot of stuff to work with, but you do know the acceleration of his jump.

If you looking for time i might try using energy (if you know how).

Ef - Ei = 0;

1/2*mv^2 - mgh = 0;

you can solve for v and that will be your initial velocity.

Otherwise I would look into the kinematic equations
 

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