A catapult launches a test rocket vertically upward from a well, giving the rocket and initial speed of 79.2 m/s at ground level. The engines then fire, and the rocket accelerates upward at 3.90 m/s^2 until it reaches an altitude of 1020 m. At that point its engines fail, and the rocket goes into free fall with an acceleration of -9.80 m/s^2. (You will need to consider the motion while the engine is operating and the free-fall motion separately.) (a) For what time interval is the rocket in motion above the ground? _s (b) What is its maximum altitude? _km (c) What is its velocity just before

Question

A catapult launches a test rocket vertically upward from a well, giving the rocket and initial speed of 79.2 m/s at ground level. The engines then fire, and the rocket accelerates upward at 3.90 m/s^2 until it reaches an altitude of 1020 m. At that point its engines fail, and the rocket goes into free fall with an acceleration of -9.80 m/s^2. (You will need to consider the motion while the engine is operating and the free-fall motion separately.) (a) For what time interval is the rocket in motion above the ground?  _s  (b) What is its maximum altitude? _km (c) What is its velocity just before

anonymous · Answer

max. altitude is the area under curve for +ve velocity.
velocity just  before [ hitting] is the final velocity , can be calculated via the graph