posted by MSM on .
Q: a freely falling object requires 1.50s to travel the last 30.0m before it hits the ground . From what height above the ground did it fall ??
Pleazzzz help ....
Let H be the height from which it is dropped. Let T be the time it takes to hit the ground. Solve these two simultaneous equations:
H = (1/2) g T^2
H-30 = (1/2) g (T-1.5)^2
By subtracting equations, H can be eliminated immediately:
30 = 1.5 g T - (1/2) g (1.5)^2
Solve for T first, then compute H.
t= 2.79 H=38.1