Physics question?

Question

A skydiver jumps from a plane 1000 meters above the ground. He waits for 8 seconds and then opens his parachute. How far above the ground is the sky diver when he opens his parachute? I really need the answer tonight! Please help if you can! Thanks.

Answer 1

Let h = 1000 m and t = 8 sec.

y = 1/2a t^2 ---> 1000 =1/2(9.8 m/s^2)*(8 sec)^2 = 314 m

Answer 2

686.08 meters above the ground

Answer 3

here's the method without the numbers

from the equation
s = s0 + viyt - 1/2gt^2
s0 = 1000
viy = 0

s = s0 - 1/2g*t^2
just plug in your numbers