An archer defending a castle is on a 15.5 m high wall. He shoots the arrow straight down at 22.8 m/s. How much time does it take to reach the ground

Answer 1

using the "free fall" equation ... h = -1/2 g t^2 + vo t + ho

0 = -1/2 * 9.81 * t^2 - 15.5 t + 22.8

use the quadratic formula to find t