Hey, I came across this site on one of my many google searchs on my quest to solve this problem, and was hoping someone could help me out.(adsbygoogle = window.adsbygoogle || []).push({});

The following word problem is the one I am trying to solve:

An object is dropped from 100 feet up. Negating wind resistance, calculate the time it took for the object to hit the ground.

What I know is as follows:

x = 100 feet

a = -9.8m/s^2

v_o = 0m/s.

The formula I have tried is 100 = v_o + 0.5(-9.8t). Obviously, it's the wrong formula as I get the wrong answer everytime (the answer I get is 6.1 or 6.2 seconds, can't remember at the moment). I chose that formula because it doesn't require the final velocity at the bottom. I suspect I need to find the final velocity, but I don't know how to go about that.

Any help would be appreciated!

BTW, I registered earlier with the name "Micah," but it never sent me an activation e-mail. Not sure if that's a problem with my e-mail provider (AOL, yay) or the forum. If possible, I'd rather use "Micah" rather than Micah18, so if the admin could resend the activation e-mail (if that is even possible) that would be nice.

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# Mechanics difficulties - acceleration

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