Question

calculate the value of time period maximum height maximum range for any object moving with 20 metre per second make an angle 60 degree with horizontal ​g=9.8 m/se²​

Answer 1

The time of flight is the interval of time between when projectile is launched: t1 and when the projectile touches the ground: t2.

At t = t1 and t = t2, y = 0 (ground). Hence

V0 sin(θ) t - (1/2) g t2 = 0

Solve for t

t(V0 sin(θ) - (1/2) g t) = 0

two solutions

t = t1 = 0 and t = t2 = 2 V0 sin(θ) / g

Time of flight = t2 - t1 = 2 (20) sin(θ) / g = 1.72 seconds.