A toy air rocket is launched vertically with an initial velocity of 22m/s. (a) How long does it take to reach its maximum height (v=0m/s? (b) How long does it take to return to the ground (x-0m)?
Hint: (a) and (b) are equal.
Consider how long it takes for the velocity to change from 22 m/s to 0, or back again.