Question

How fast is a ball going when it hits the ground after being dropped from a height of 9 m? The acceleration of gravity is 9.8 m/s

Answer 1

`\huge\boxed{\sf v_f = 1.48\ m/s}`

Step-by-step explanation:

Given Data:

Height = h = 9m

Acceleration due to gravity = g = 9.8 m/s²

Initial Velocity = Vi = 0 m/s

Required:

Final Velocity = Vf = ?

Formula:

`2gh = v_f^2 - v_i^2` (Third equation of motion for free-falling bodies)

Solution:

2(9.8)(9) = vf² - 0²

2.18 = vf²

vf² = 2.18

Take sq. rt on both sides

vf = 1.48 m/s

`\rule[225]{225}{2}`