Focal point of reflection
Brahe & Kepler
Answer from Quizlet
By counting the protons in the element
vf = vi + at
vf – vi = at<span>
<span>vi= 0, vf=26 and afor nil = 9.8m/s2</span></span>
26 = 9.8t
t =<span> 26 / 9.8 = 2.65 s
Now we know the total time, so we can calculate the time 1
second before it hit the ground.
<span>= 2.65 -1 = 1.65s
<span>Now again using the same equation, vf = vi+at, we can find vf
vi = 0, a = 9.8 t=1.65</span></span></span>
vf = 0 + 9.8(1.65) =
16.17 m/s<span>
</span><span>So,
the nail is traveling with the speed of 16.17m/s 1 second before it hits the
ground.</span>
