How Does Adding Mass Affect the Thrust of a Model Rocket?

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Adding mass to a model rocket does not change the thrust produced by the engine, which remains at 2N for the Estes A8-3. However, the additional mass affects the rocket's acceleration, as acceleration is inversely related to mass according to Newton's second law. The original mass of the rocket is 35g, and with the added 100g, the total mass becomes 135g. While thrust remains constant, the increased mass will result in lower acceleration. Understanding this relationship is crucial for analyzing the rocket's performance after mass addition.
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Homework Statement


Hi. I'm in high school physics, and as I'm only 2 months in, I still don't know much. We launched a model rocket as an experiment and I need to find the thrust after adding 100g of mass to the rocket's body.

The engine is an Estes A8-3. My teacher told me that its thrust is 2N in less than 1s.
The original mass of the model rocket is 35g, and we added 100g of mass to the body.
I'm trying to find the thrust after the 100g was added, and then the average between the before and after.

We haven't been taught anything about thrust and I don't have my book with me so I'm lost! I'm sorry if I didn't include important info, or if I seem like I don't know anything because I honestly don't in this case!

Thank you,
Sienna
 
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If the engine is the same, I don't see why the thrust should change. Are you sure you're asked to find the new thrust and not the new acceleration?
 
Nathanael said:
If the engine is the same, I don't see why the thrust should change. Are you sure you're asked to find the new thrust and not the new acceleration?
See that's why I was confused! I'm sure he said thrust. I have no clue what he means, but I'll ask him later. Thanks anyway :)
 
Thrust will depend a bit on velocity and velocity depends on the mass, but I think you can neglect this for your analysis here. Acceleration will certainly depend on mass.
 
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The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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