Density Error Propagation/Significant Figures Based on Extreme Values

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The discussion focuses on calculating the density of an object with a mass of 976 g and a volume of 1 L, while factoring in significant figures and error propagation. The upper limit for density is calculated using the maximum mass and minimum volume, while the lower limit uses the minimum mass and maximum volume. There is confusion regarding how to apply significant figures, particularly since the mass has three significant figures and the volume has only one. The conclusion suggests calculating both density extremes using all digits and determining the appropriate number of significant figures from the resulting values. This approach aims to ensure accuracy without losing significant information.
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Homework Statement


The density of an object is found to be 976 g/L based on mass of 976 +/- 5g and volume of 1 +/- 0.01L.

Determine the error in the density using extreme values (upper limit of mass divided by lower limit of volume, etc)

Homework Equations


I'm having difficulty determining how to factor in significant figures here.

Use D = M / V

The Attempt at a Solution


Upper limit = (976 + 5) / (1 - 0.01)
Lower limit = (976 - 5) / (1 + 0.01)

My reasoning: since the numerator result has 3 significant figures, and the denominator has 1 significant figure (since 1 only has 1sigfig), the resultant densities have 1 sigfig. But this seems to cut off too many figures.
 
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Not all zeros are insignificant. Calculate both densities using all given digits and decide from those values the number of significant digits of the density.

ehild
 
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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