Free falling - Am I doing right?

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The calculation for the time of impact for a free-falling object from 300 meters is correctly derived using the equation y = -4.9t^2 + 300. By setting the equation to zero and solving for t, the result is approximately 7.8 seconds. The discussion confirms that the calculations are accurate, assuming no air resistance. Participants express agreement and validate the approach taken. Overall, the method used to determine the time of impact is correct.
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Hi. I'm going to calculate the time of impact for a free falling object, witch falls from 300 meters without any initial velocity.

So far I'm thinking I can do something like this.
y=-4.9t^2 + 300
-4.9t^2 + 300 = 0
4.9t^2 = 300
t^2 ~= 61
t ~= 7.8

Answer: The impact takes place 7.8 seconds after the drop of the object.

I'm assume I'm doing something wrong, so I'm really glad if anybody takes some time and look at this.
 
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Looks good to me (neglecting air resistance, of course).
 
You got it right!
 
Unbelieveable
 
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