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

A model rocket releases its first stage when it is 100.0 m above the ground and moving upward at 40.0 m/s. Ignoring air resistance, find:

the time it takes the first stage to hit the ground

2. Relevant equations

Y=Yo+VyoT+1/2GT^2

Quadratic

3. The attempt at a solution

I got to [-(40)+-Squareroot(1600-1960)]/9.8

the problem is that the square root of a negative number is an imaginary number so I am just wondering what I am missing here?

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# Homework Help: Time for rocket shot upward to reach the ground

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