Solving Squid Propulsion with Momentum Conservation Equation

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The discussion focuses on applying the momentum conservation equation to a problem involving a squid's propulsion. The initial mass of the squid is 1.2 kg, which decreases to 1.1 kg after expelling water. The conservation of momentum principle is used to set up the equation: 1.2 kg * 0.6 m/s = 1.1 kg * 2.7 m/s - 0.10 kg * vwater. The resulting calculation indicates that the speed of the expelled water is 22.5 m/s, which raises questions about its magnitude. The participant expresses confusion about the calculations but ultimately confirms the conservation of momentum principle is correctly applied.
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Homework Statement


squidward.PNG


Homework Equations


p=mv
j=Δp[/B]

The Attempt at a Solution


I am confused as to how to approach this problem. so it looks like squidwards mass is changing from 1.2kg to 1.1kg after he shoots out the water from his butt. I know that momentum is conserved so

1.1*2.7 - 1.2*0.6 should = 0.
this leaves -2.25kgm/s left. so then i would have to divide by his mass? so his mass is currently 1.1kg which gives a speed of 2.0454545m/s
 

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ok i am completely wrong here and don't know what i am doing
 
Ahh ok i got it.
So the momentum is conserved

1.2kg*.60m/s = 1.1kg*2.7m/s - .10kg*vwater

-2.25kgm/s / -.10kg = vwater = 22.5m/s
Why is that so small ? i tried to edit it


-2.25kgm/s / -.10kg = vwater = 22.5m/s​
 
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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