Need help with impulsive tension in an inextensible string.

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SUMMARY

The discussion focuses on calculating the impulsive tension in an inextensible string connecting three particles A, B, and C, each with mass m, positioned at a 120-degree angle. An impulse J is applied to particle B at an angle of 150 degrees with respect to BC and 90 degrees with respect to BA. The derived results indicate that the impulsive tensions are J√3 / 15 and 4J√3 / 15, while the initial velocities are v A: J√3 / 15m along AB, v B: 2J√21 / 15m at arctan 3√3 to AB, and v C: 4J√3 / 15m along CB.

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  • Basic trigonometry for angle calculations
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franklinear
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1. The problem statement, all
variables and given/known
data


Three particles A, B and C all of mass m rest on a smooth horizontal plane so that angle ABC is 120 degree. B is connected to both A and C by light inextensible string which are initially just taut. An impulse J is then applied to particle B in a direction making an angle of 150
with BC and 90 with BA.
Find impulsive tension in each string and the initial velocity of each particle.

2. Homework Equations

3. The Attempt at a Solution
I could do one similar question i.e. when the impulse is applied to B making a horizontal direction to the right. The horizontal velocity of A and B would be the same but A also experiences vertical move. However for this question, I can't solve it. I've tried many times but still don't get the point.


key answers given:
J √3 / 15; 4J√3 / 15
v A: J√3 / 15m along AB
v B: 2J√21 / 15m at arctan 3√3 to AB
v C: 4J√3 / 15m along CB

Please help me. Thanks in advance!
 
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I've replied to your other post on TSR.
 
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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