Question

Jason hits a volleyball with an initial velocity of 6 meters per second straight up. if the back starts at 2 meters above the floor how long will the ball be in the air

Answer 1

Vi = 6 m/s
d = -2 m
a = - 9.81 m/s^2
t = ?
Formula
d = vi*t + 1/2 a t^2
- 2 = 6m/s *t - .5 * 9.81 * t^2
Put the - 2 on the right.
4.905 t^2 + 6 m/s t +2 = 0
a = -4.905 m/s^2
b = 6 m/s
c = 2 m
t = [- b +/- square root(b^2 - 4ac)]/(2a)
t = [ -6 +/- square root (6^2 - 4*(-4.905)*2)] / (- 4.905*2)
t = [-6 +/- 8.674) / - 9.81
t = -14.674/-9.81
t = 1.69 seconds.