The distance s(in m) above ground for a projectile fires vertically upward with a velocity of 54 m/s as a function of time (in s) is given by s=54t-4.9t^2. Find t for v=0

Answer 1

The first thing to remember is that the velocity function is the derivative of the position function ( s(t) ).

s(t)=54t-4.9t²

v(t) [or s'(t)] = 54-9.8t

Next, we solve for t when v=0.

0=54-9.8t

9.8=54t

t = 9.8/54 = 0.1815s