a 2 liter bottle rocket has a thrust phase on .25 sec. The rocket goes straight up, reaches its apex, then plunges straight down. Total time is 8 sec. How do I calculate height, velocity and acceleration???
You need to solve four equations in four unknowns: a, V, h, H.
acceleration during thrust = a
height at end of thrust = h
maximum height = H
Here are the four equations:
velocity at burnout = V = 0.25 a
maximum height = H = h + V^2/(2g)
h = (1/2)*a*0.25^2
h + V*(7.5) -g(7.5)^2 = 0 (height 7.5 s after burnout)