Question

A tennis ball machine serves a ball vertically into the air from a height of 2 feet, with an initial speed of 130 feet per second. After how many seconds does the ball attain its maximum height?

Answer 1

h(t) = - 16t² + v0 + h0

where h = height, t = time, v0 = initial velocity and h0 = initial height

v0 = 130
h0 = 2

h(t) = - 16t² + 130t + 2

Max. Ht.: h'(t) = 0:

h'(t) = - 32t + 130

- 32t + 130 = 0
- 32t = - 130
t = - 130 / - 32
t = 4.06 sec.

Answer 2

Thank You !!