contestada

a
A soccer player kicks a ball horizontally and it travels 150 m. The ball was kicked off of a cliff that was 75 m
high. What speed was the ball kicked at?

Respuesta :

The ball was kicked with a speed of 38.4 m/s.

Using s = ut + 1/2gt², we find the time it takes the ball to reach the ground. Where

  • s = height of cliff = 75 m
  • u = initial vertical velocity of ball = 0 m/s(since it is kicked horizontally)
  • g = acceleration due to gravity = 9.8 m/s²
  • t = time taken for ball to reach the ground.

Substituting the values of the variables into the equation, we have

s = ut + 1/2gt²

75 m = (0 m/s)t + 1/2 × 9.8 m/s² × t²

75 m = 0 m + (4.9 m/s²) t²

75 m = (4.9 m/s²)t²

Dividing both sides by 4.9, we have

t² = 75 m/4.9 m/s²

t² = 15.306 s²

Taking square-root of both sides, we have

t = √15.306 s²

t = 3.91 s

The horizontal distance covered by the ball d = vt where

  • v = horizontal speed of ball and,
  • t = time taken for the ball to reach the ground.

Since we require v, we make it subject of the formula.

So, v = d/t

Given that d = 150 m and t = 3.91 s, substituting these into v, we have

v = d/t

v = 150 m/3.91 s

v = 38.4 m/s

So, the ball was kicked with a speed of 38.4 m/s.

Learn more about motion under gravity here:

https://brainly.com/question/25271752