Question

A small ball shot vertically upward from the top of building 15 m above ground with initial velocity 9.81m/s. Determine the maximum height the ball will reach?

Answer 1

Explanation:

direct formula to find maximum height is 2u/g

u=9.81m/s

g=9.8m/s^2

2×9.81/9.8=2.002 mtr

Answer 2

let initial velocity = 10 m/s

final velocity = 0

acceleration due to gravity = 10 m/ s^2

from third equation of motion

v^2- u^2 = 2as

-100 m/s = 2× -10s

s = -100/-20

s = 5 meter

Maximum height attend by the ball = 15+5 = 20 meter.