Question

a foot ball is kicked vertically up ward in order to a height of 45m. how long will it take be in the air?

Answer 1

We have,

d = 45 m

a = -9.8 m/s^2

v final = 0 m/s

2 * a * d = v^2 - u^2

u^2 =  882

u = 29.7 m/s

now using , v = u + at

t = 29.7 / 9.8 = 3s

now the ball would come back to the ground taking the same time,

so total time taken is 3+3 = 6s