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 C42711 Dec12-11 05:04 PM

Determining Acceleration

A feather is dropped on the moon from a height of 1.40 meters. The acceleration of gravity on the moon is 1.67 m/s2 Determine the time for the feather to fall to the surface of the moon.

So, I wrote my given:
d=1.4 m
a= 1.67 m/s2
both initial and final velocity= 0

I know I am looking for time, but I have no idea what equation to use. I tried:
vf= vi+at , but I didn't get the right answer. The answer should be 1.29 s.
Any help would be much appreciated, please and thank you!:)

 rock.freak667 Dec12-11 05:07 PM

Re: Determining Acceleration

Well what equation involves d,a,t and u (initial velocity)?

 C42711 Dec12-11 05:13 PM

Re: Determining Acceleration

This does: d=vi+1/2*at2
but I didn't get the right answer with that either, I got .75:(

 C42711 Dec12-11 06:01 PM

Re: Determining Acceleration

I got the right answer now.:)

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