Answer:
4.48 seconds
Explanation:
Initial VERTICAL velocity COMPONENT is given by
140 sin 31° = 72.1 f/s
The velocity at any given time is given by
Vf = vo + a * t Vf = final velocity vo = 72.1 f/s a = -32.2 f/s^2
when the ball reaches its peak, Vf = 0 this is 1/2 of the fight
0 = 72.1 - 32.2 t shows t = 2.24 seconds for 1/2 flight
total fight time = 2 x 2.24 = 4.48 seconds