Calculating the Initial Vertical Acceleration of a Saturn V Rocket

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The discussion focuses on calculating the initial vertical acceleration of a Saturn V rocket, given its mass of 2.75x10^6 kg and a force of 3.3x10^6 N. The user attempts to solve the problem using Newton's second law but arrives at an incorrect acceleration of -8 m/s^2. They question whether the force value should actually be 3.3x10^7 N instead, as this would yield the correct acceleration of 2.2 m/s^2. Other participants confirm the force value is indeed 3.3x10^6 N, suggesting that the textbook may contain an error. The conversation highlights the importance of verifying provided data in physics problems.
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Homework Statement


A Saturn V rocket has a mass of 2.75x10^6 Kg and exerts a force of 3.3x10^6N on the gases it expels.
determine the initial vertical acceleration of the rocket.



2. The attempt at a solution
heres my attempt...
F=3.3x10^6N
Fg=
M=2.75x10^6
Fnet-MA
F-Fg=ma
F-mg=ma
3.3x10^6-(2.75x10^6)(9.8)=2.75x10^6a
3.3x10^6-2.6x10^7=2.75x10^6a
-2.2x10^7=2.75x10^6a
-2.2x10^7/2.75x10^6=a
a=-8

The accual answer is 2.2m/s^2
Can someone explain to me what i got wrong?
 
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Are you sure it's 3.3x10^6N and not 3.3*10^7 N? You get the correct answer with 3.3*10^7 N.
 
ideasrule said:
Are you sure it's 3.3x10^6N and not 3.3*10^7 N? You get the correct answer with 3.3*10^7 N.

No I am sure its that
this question is straight from a textbook.
 
In that case, the textbook made a mistake.
 
ideasrule said:
In that case, the textbook made a mistake.
It must have!
 
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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