(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A student standing on the ground throws a ball straight up. The ball leaves the student's hand with a speed of 15 m/s when the hand is 2.0 m above the ground. How long is the ball in the air before it hits the ground? (The student moves her hand out of the way.)

2. Relevant equations

X= Vt + .5at^2

3. The attempt at a solution

I'm not sure why I can't get this right. At first I thought it impossible without the acceleration, but then I discovered that because the acceleration is merely the slope of the velocity graph, it would just equal '2/t', right? I have my X (delta x) as 2. (Would it be negative 2??) My initial velocity is 15 m/s (as stated) and my variable is t. I ended with this equation:

2= 15t + .5(2/t)t^2

Why can I not get the answer from this equation? I keep getting extremely low decimals.

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# Homework Help: A Student throws a ball straight up

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