A stone throw horizontally from the top of a wall with a velocity of 15m/s, hits the ground at a point of 45m from the wall. Find the time of the flight

Question

"A stone throw horizontally from the top of a vertical wall with a velocity of 15m/s, hits the horizontal ground at a point of 45m from the base of the wall.

Calculate

1)Time of flight of the stone

2)Height of the wall"

Answer 1

1)  distance = rate*time, so distance/rate = time

• distance = 45 m
• rate = 15 m/s

 

      time = (45 m)/(15 m/s) = 3 s

 

2)  height = (1/2)gt²

• g = acceleration due to gravity = 9.8 m/s²
• t = time = 3 s (from problem 1)

 

      h = (1/2)(9.8 m/s²)(3 s)²

      h = 4.9*9 = 44.1 m