posted by Patrick .
A ball is thrown upward. What is its initial vertical speed? The acceleration of gravity is 9.8 m/s^2 and maximum height is 7.2 m,. Neglect air resistance. Answer in units of m/s
h = vt - 4.9t^2
max height reached at t=v/9.8 sec
7.2 = v(v/9.8) - 4.9(v/9.8)^2
v = 11.9m/s