a projectile is launched with an initial velocity of 60m/s at an angle of 30deg above horizontal?

Question

what is the max height reached by the projectile and how long will it stay in the air

Answer 1

Break the motion into components along the x- and y-axes. However, in this particular problem, we can ignore the horizontal problem.

Vertical:

yo = 0
voy = vo sin 30 degrees
ay = -g
y = final height ( unknown )

Equations needed:

vy = voy + ay t
y - yo = voy t + 1/2 ay t²

Plug what you know into the first equation ( note that at the max height, vy = zero ) and solve for the elapsed time t. Then use that time in the second equation to find the height yo.