Question

A stone falls from a ledge and takes 8 seconds to hit th ground . the stone has an original velocity of 0 m/s how tall is the ledge ?....A...1,254.4 meters ....B....313.6 meters.....C..... 78.4 meters .......D....... 39.2 meters

Answer 1

To answer this question, remember the formula ∆X = Vot + 1/2 at^2
To solve, all you have to do is plug in the numbers.
∆X = height of the ledge (the unknown)
t = time (8 seconds)
a = acceleration (9.8 m/s^2)
Vo = initial velocity

∆X = 0(8) + 1/2(9.8m/s^2)(8s)^2
∆X = 0 + 313.6 m
∆X = 313.6 meters

Your answer would be B, 313.6 meters