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

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The discussion centers on calculating the time it takes for a kid to jump one meter into the air and land back down. The calculated time for the descent is approximately 0.45 seconds, while the total time including the ascent is 0.95 seconds, based on the assumption of upward acceleration at 9.8 m/s². There is a query regarding the initial velocity of the jump, with suggestions to use energy conservation or kinematic equations for further analysis. The conversation emphasizes the importance of understanding both the upward and downward motions in calculating total time. Overall, the calculations hinge on the principles of physics, particularly gravity and 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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