Finding gravity through experimental data

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The discussion focuses on determining the acceleration due to gravity (g) using experimental data from a freely falling object. Two methods for finding g from a straight line graph representation are suggested: one involves plotting distance (x) against time squared (t^2), where the slope represents 0.5g, and the other method suggests using a linear transformation of the original equation to fit the y = mx + b form. The vertical variable in both methods is distance (x), while the horizontal variable is time squared (t^2). The participant acknowledges the known value of g as 9.81 m/s² and contemplates using Excel to derive a numerical estimate based on the provided data. The discussion emphasizes the importance of graphing and data analysis in validating theoretical physics concepts.
BayernBlues
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Homework Statement


Experimentally measured time of fall
vs. distance for a freely falling object
Distance, x (m) Time, t (s)
0.1 0.148
0.2 0.196
0.3 0.244
0.4 0.290
0.5 0.315
0.6 0.352
0.7 0.385
0.8 0.403
0.9 0.429
1.0 0.451
Let the mathematical model be: x = 0.5gt^2 and assume that x = 0 at t = 0 :
a. In the light of what you learned in problem 1.1 (parts a and b) and the form of the equation
x = 0.5gt^2 , discuss (without calculations) two different methods that can be used to find g, the
acceleration due to gravity, from a straight line graph representation. In each method, indicate
explicitly the vertical variable, horizontal variable, slope, and intercept. Draw sketches.
b. Find a numerical estimate for g based on the above table, using the EXCEL program?



Homework Equations



x = 0.5gt^2

The Attempt at a Solution




I know that the value of g is 9.81 m/s^2 but this is asking how to show it through experimental data and graph. I think maybe taking the ln of both sides to change this into y=mx+b form might help but am unsure. Also, I thing g would be the constant in the equation if it was changed to y = mx + b form therefore it'd be the slope value.
 
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It gives you the values of x and t, you have the equation that relates them. Solve for g.
 
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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