A golf ball í hit off the ground at an angel pi/6 travels 400ft. how long in the air

You can write the equations of motion as

h (t) = - 16t² + v₀sin (θ) t

d (t) = v₀cos (θ) t

Solving the second of these for t and substituting into the first equation gives the time of flight as

0 = - 16t² + d (t) ·tan (θ)

t = √ (d (t) ·tan (θ) / 16)

So, for d (t) = 400 and θ = π/6, this becomes

t = √ ((400/16) / √3)

t = 5/√ (√3) ≈ 3.79918

The ball is in the air about 3.80 seconds.