A football is kicked off the ground at an initial upward velocity of 20 m/sec.

(We are using d=rt-5t^2)

a. Calculate the altitude after 2.7 sec
b. When will the ball be at 17 m above the ground?
c. When is the ball at the highest point?
d. How high is the ball at its highest point?

2 answers

altitude= Vi*time- 4.9 time^2
use that for a, b.

For c, note that velocity at the top is zero.

Vtop=Vi*time-4.9t^2
solve for time

d. use the first equation again.
a.10