Question

The average height of an apple tree is 4.00 meters. How long would it take an apple falling from that height to reach the ground?
Given: g = -9.8 meters/second2

Answer 1

S for distance
a for acceleration (in your case g)
v0 for starting sped (in this case = 0)

S= v0*t + (a*t^2)/2= (a*t^2)/2
a*t^2=2S
t^2=(2*S)/a
t= square root ->((2*S)/a)