Having trouble with Helmholtz Coil Experiment Calculations

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SUMMARY

The discussion centers on the calculations involved in the Helmholtz Coil Experiment, specifically addressing the magnetic moment and gravitational torque equations. Key parameters include 100 wraps for the magnetic moment (N_c), 140 wraps for the Helmholtz coil (N_h), and a current of 0.796A (I_c). The magnetic field (B_h) is calculated using the formula Bh=(8u_0*N_h*I_h)/(5^(3/2) * R_h), while the magnetic torque (T_m) is derived from T_m = B_h * N_c * I * A_c. Participants highlight discrepancies in torque calculations, suggesting potential conversion errors or misinterpretations of the area vector's orientation.

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Homework Statement


Number of wraps of coil on magnetic moment in field: 100 - N_c
Number of wraps of coil on Helmholtz coil: 140 - N_h
Current through magnetic moment: .796A - I_c
Area of magnetic moment: .37m - A_c
Radius of Helmholtz coil: .1635m - R_h
Current through Helmholtz coil to attain equilibrium on balance: 1.32, 2.61,3.91 corresponding to gravitational torques caused by counterweights that are .255m away, .0001g,.0002g,.0003g


Homework Equations


Bh=(8u_0*N_h*I_h)/(5^(3/2) * R_h)
as well as T_m = B_h * N_c*I*A_c

The Attempt at a Solution


I calculated the three torques both gravitational as well as magnetic based on the formulas provided above. Each time I received an answer that was a magnitude of 100 apart. Based on my thinking the T_g and T_m should be equal as the magnetic torque should balance out the gravitational torque. I have checked to make sure all of my units are in SI and I still cannot determine why I am not getting the calculations that I should. I also cannot make heads or tails of how the Area of the magnetic moment within the field should have a vector and if it does, how to describe its orientation in space.
 
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Do you get "exactly" 100 as factor between the answers? This would hint to some conversion errors, or a missing factor of N_c somewhere.
If the factor is 125, the factor of 5^(3/2) is in the wrong part of the fraction.
Can you show your calculations? I don't see an obvious error here. I think the prefactor 8/(5^(3/2)) is given somewhere?

A notation like "100 - N_c" is confusing, this looks like a subtraction. Why don't you write 100 = N_c, or (better) N_c = 100?
 
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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