Net Force of a Model Rocket in Free Fall

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The model rocket experiences a net force of 2.0 N while ascending under thrust. Once the fuel is exhausted, the rocket enters free fall, where the only force acting on it is gravity, resulting in a net force of -4.9 N (downward). As it ascends and reaches its peak, the net force remains -4.9 N during the turnaround. When falling back to the ground, the net force continues to be -4.9 N until it impacts the ground. The discussion emphasizes the change in net force due to the transition from powered flight to free fall.
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A model rocket with a mass of 0.50 kg is fired vertically from the ground. Assume that it is streamlined enough that air resistance can be ignored. Suppose it ascends under the influence of a constant net force of 2.0 N acting in a vertical direction and travels for 6.0 s before its fuel is exhausted. Then it keeps moving as a particle-like object in free-fall as it continues upward, turns around, and falls back down.

What is the net force on the rocket when it continues upward as a free fall particle? as it turns around? When it is traveling back toward the ground?
 
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Welcome to PF!

Hi wicked_vixen! Welcome to PF! :smile:
wicked_vixen said:
… before its fuel is exhausted. Then it keeps moving as a particle-like object in free-fall as it continues upward, turns around, and falls back down.

What is the net force on the rocket when it continues upward as a free fall particle? as it turns around? When it is traveling back toward the ground?


What do you think?

What forces are acting on the rocket once the fuel stops?

Do they change, and if so, how? :smile:
 

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