Answer:
4.69 s
Explanation:
u = Initial velocity = 30 m/s
[tex]\theta[/tex] = Angle of launch = [tex]50^{\circ}[/tex]
g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
Time taken by the projectile to land is given by
[tex]t=\dfrac{2u\sin\theta}{g}\\\Rightarrow t=\dfrac{2\times 30\times \sin50^{\circ}}{9.81}\\\Rightarrow t=4.69\ \text{s}[/tex]
The time the projectile is in the air before it contacts the ground again is 4.69 s.