An adult dolphin weighs around 1410 N. How fast must he be moving as he leaves the water vertically in order to jump to a height of 1.50 m? Ignore air resistance.

D = 1.50 m (max height)

vf² = vi² + 2 a d

where: vf is the final velocity, vi is the initial velocity and a = - g = - 9.81 m/s²

vf = 0

0² = vi² - 2 · 9.81 · 1.50

vi² = 29.43

vi = √29.43

vi = 5.42 m/s

Answer: His velocity as he leaves the water must be 5.42 m/s.