How Is Binding Energy Calculated for Lithium-6 Nuclei?

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The discussion focuses on calculating the binding energy for Lithium-6 nuclei, with participants addressing the formula used and the correct interpretation of given values. The initial calculation yielded a binding energy of 30.2 MeV, which was incorrect, leading to confusion about the binding energy per nucleon. After clarification, it was confirmed that using the binding energy per nucleon (5.33 MeV) multiplied by the number of nucleons (6) should yield the total binding energy. The corrected calculation resulted in a binding energy of approximately 31.98 MeV, aligning with the expected outcome. The conversation highlights the importance of understanding the relationship between binding energy and the number of nucleons in nuclear physics.
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Homework Statement


How do I find the binding energy for the nuclei of Lithium 6.
N=Z=3, atomic mass=6.015 u, binding energy per nucleon= 5.33 MeV
The equation I'm using is :

B(N,Z)=Z*m(0,1)*c^2+N*(mass of n)*c^2-m(N,Z)*c^2.

B(N,Z)=3*(1.00783u*1.66E-27kg)*(3E8 m/s)^2+3*(1.008664u*1.66E-27kg)*(3E8 m/s)^2-(6.015u**1.66E-27kg)*(3E8 m/s)^2

B(N,Z)= 4.84056E-12 J *6.24E18 eV= 30.2 MeV

but that's not the answer, I also tried dividing that answer by the binding energy per nucleon which is 5.332 MeV and I got 5.66 MeV that's not the answer. I'll appreciate it if someone explained to me what I'm doing wrong. Thanks.
 
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You are given the binding energy per nucleon and you know the number of nucleons so you should be able to get the binding energy of the NUCLEUS.
Is that what the question means?
 
Well, you are right, I didn't catch that , now I got 31.98 MeV, which is close to the same answer I got doing all the needless calculations but not quite, since now I got it right. Thanks!
 
that is good to hear ! sometimes we are blinded by information!
 
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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