The model rocket in Problem 134 has a mass of 87 g and you may assume the mass of the fuel is much less than 87 g.
(a) What was the net force on the rocket during the first 1.5 s after liftoff?
(b) What force was exerted on the rocket by the burning fuel?
(c) What was the net force on the rocket after its fuel was spent?
(d) The rocket's vertical velocity was zero instantaneously when it was at the top of its trajectory. What were the net force and acceleration on the rocket at this instant?