An object is dropped from a balloon from a height of 500m. (a) How long does it take to reach the ground?
(b) If the object has an initial velocity of 12m/s, how long does it take to reach the ground? How far will it fall in 5 secnds?
s = 1/2 at^2
500 = 4.9t^2
Now you have the time.
You need to say what the velocity's direction is. As you recall,
s = vt + 1/2 at^2
It makes a big difference whether v is positive or negative.
In 5 seconds it will fall 4.9*5^2 meters.posted by Steve