Calculating the Accepted Value of g with a Pendulum

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To calculate the accepted value of g using a pendulum, the formula g = 4π²L/T² is essential, where L is the length of the pendulum and T is the period. The discussion highlights the need to express the error in g, represented as σg, using the formula σg/g = √[(σL/L)² + 2(σT/T)²]. Participants express confusion about how to manipulate the equations and incorporate measurement errors effectively. The conversation emphasizes starting from the fundamental equation and systematically breaking it down to understand the relationships between variables and their uncertainties. Clarity on these calculations is crucial for accurately determining the value of g.
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Homework Statement



Find the accepted value of g


Homework Equations




(sigma)(g) = |g|[(sigma(L))/|L| + 2 (sigma(T))/|T|]
Acceleration due to gravity for a pendulum broken down.


The Attempt at a Solution



I really do not have a clue. If I had to guess, I would say 2. Can anybody please offer me some help with this problem?
 
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Please write the expression for g in terms of L and T?

Then write the expression for the error of g, or σg, or better σg2.

Is one given the errors (σ) of measurement?
 
Would it be...

sigma g/g = sqr[((sigma L)/L)^2 + 2((sigma T)/T)^2]

gbest = (4pi)^2 x L/T^2

The first one would give the errors of measurement?
 
sigma g/g = sqr[((sigma L)/L)^2 + 2((sigma T)/T)^2]
Is this the formula that one is given?

If so, the what is the expression of g in terms of the other variables?
 
O.k. I totally confused...let's start from the beginning. The original equation was:

g = 4(pi^2)L/T^2, then, to the best of my knowledge I'm supposed to break down the equation to:

g = 4(pi)^2LT^-2, and this is where I get confused because I've never dealt with something like this before, and I wasn't given much instruction. i also appreciate you being patient with me.

So, after this I assume I'm supposed to break down the equation into an error equation:

sigma g/g = sigma (4)/|4| + 2(sigma (pi)/|pi|) + sigma (L)/|L| + |-2|(sigma (T)/|T|)

Now, I get this equation from an example but I get confused on what to do with it after this point. I know 4 and pi are constants and can be removed from the equation but I don't really know where to take it from here.
 
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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