A ball is thrown 107 m upward and then falls back to earth.

Question

Neglecting air resistance, how long will it
be in the air? The acceleration of gravity is 9.8 m/s2 .
Answer in units of s

Answer 1

V^2 = Vo^2 + 2g*h
Vo^2 = -2g*h = -2*-9.8*107 = 2097.2
Vo = 45.8 m/s.

V = Vo + gt = 0 @ max. ht.
Tr = (V-Vo0/g = (0-45.8)/-9.8 = 4.67 s. = Rise time.

Tf = Tr = 4.67 s. = Fall time.

T = Tr + Tf = 4.67 + 4.67 = 9.35 s. =
Time in air.