Your tennis ball rolls off a 0.91m tall table and hits 0.25m out from the table. What is it's time in the air? What is its vertical velocity before hitting the ground (show work)

consider the motion of the ball in vertical direction after it rolls off the table

v₀ = initial velocity of the ball in vertical direction = 0 m/s

a = acceleration = acceleration due to gravity = 9.8 m/s²

Y = vertical displacement = height of the table = 0.91 m

t = time spent in air by the ball

Using the kinematics equation

Y = v₀ t + (0.5) a t²

0.91 = 0 t + (0.5) (9.8) t²

t = 0.43 sec

v = final velocity in vertical direction just before it hits the ground

Using the kinematics equation

v = v₀ + at

v = 0 + (9.8) (0.43)

v = 4.21 m/s