Acceleration due to gravity using a compound pendulum experiment

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The discussion focuses on plotting a graph of l(1+L^2/12l^2) against T^2 to determine the acceleration due to gravity using a compound pendulum. The user reports inconsistent values that do not yield the expected slope of 9.8 when applied to the formula g=4pi^2/slope. Suggestions include using the current results while addressing potential measurement errors and uncertainties, as well as improving experimental methods. It is recommended to plot L(T^2) against L^2 instead, which should yield a straight line with the gradient representing g. Overall, the emphasis is on analyzing the results critically rather than attempting to adjust them artificially.
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I am required to plot a graph of l(1+L^2/12l^2) on the x-axis and T^2 on the y axis.The graph must be a straight line through the origin.I got the following values for the l values on the x-axis .57,.47,.37,.27,.17 and corresponding values of T^2 2.46,2.52,2.56,3.24,8.12.As you can see my values are totally off and do not give the necessary slope needed to give 9.8 when subbed into the formula g=4pi^2/slope.Please advise on how i would go about changing the values to suit as I'm unable to do the experiment again

the original formula is T=2pi(sqr l/g) (1+L^2/12l^2)

Big L is 1.2m






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You should probably just use the results you have now and then comment on what made them so shoddy. Comment on uncertainties in the measurements and methods to improve your experiment. I think lecturers would prefer bad results with evidence that you've thought about the problems than good results.
 
the graph you should be plotting is L(T^2) against L^2 This should be approximatly a straight line, and the gradient should give you g, I think...
 
please tell me the errors that could be occur in the practical compound pendulum...?
 
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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