A rifle shoots a bullet upward from an initial height of 5m. After 3s, its height is 20m. What is the bullet's velocity at this time?
h = Vo*t + 0.5g*t^2 = 20-5.
Vo*3 - 4.9*3^2 = 15.
3Vo = 15 + 44.1 = 59.1.
Vo = 19.7 m/s. = Initial velocity.
V = Vo + g*t.
Vo = 19.7 m/s.
g = -9.8 m/s.
t = 3 s.
V = ?
Note: V will be negative which means that the bullet has passed it's peak and
moving downward.