Jennifer serves the volleyball to Debra with an upward velocity of 10.5ft/s. The ball is 5 feet above the ground when she strikes it. How long does Debra have to react, before the volleyball hits the ground? Round your answer to two decimal places.

Answer 1

since the height y is given by

y = 5.0 + 10.5t - 4.9t^2

just solve for t in

5.0 + 10.5t - 4.9t^2 = 0