"best" value for volume of a box

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    Box Value Volume
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Homework Help Overview

The discussion revolves around determining the "best" value for the volume of a box, given its dimensions with associated uncertainties. The subject area includes concepts of volume calculation and uncertainty in measurements.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to calculate the volume using the formula V=lwh but struggles with the concept of the "best" value and how to incorporate uncertainties. Some participants question the definition of "best value" and suggest that more information may be needed to clarify the problem. There is also a discussion about how to evaluate the uncertainty in the volume calculation.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem. The original poster expresses confusion about the requirements and later realizes a unit conversion error. Guidance has been offered regarding the importance of clearly stating how answers are evaluated and the need to show working and reasoning.

Contextual Notes

The original poster mentions constraints related to an online assignment with limited attempts, which adds pressure to understand the requirements accurately. There is also a reference to the need for clarity in the problem statement and the evaluation of uncertainties.

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Homework Statement


I'm given length, width and height of the box, all have uncertainties.

Homework Equations


V=lwh

The Attempt at a Solution


I've tried V=lwh, wasn't correct. Then V=lwh x (1 + relative uncertainty), wasn't correct. I just have no idea what the "best" value of a box is, my lab manual doesn't say anything about it, and I can't find anything on google either and I'm running out of tries. Appreciate any help![/B]
 
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You need to define "best value" for this problem - what does that mean?

Please provide the complete problem statement.
If you have ##l\pm\sigma_l##, ##w\pm\sigma_w## and ##h\pm\sigma_h## as independent measurements of the dimensions of a rectangular box, then the volume of the box is ##V=lwh\pm\sigma_V##.

So if that is not correct (how do you know?) then there is some information missing from the problem statement, or the solution attempt. i.e. how did you evaluate ##\sigma_V##?
 
That's the thing..I don't know what the "best" value is, and nowhere I've looked has told me what it means. And it's for an online assignment which I have 10 tries for, so it tells me whether the answer is right or wrong.

EDIT: Never mind. I can't believe how stupid the mistake I was making was..I just wasn't paying attention to the units. Measurements were given in cm, question wanted m^3. Sorry for wasting your time.
 
No worries - sometimes talking to someone else is what it takes to see the obvious right under your nose :)

BTW: whenever you have an answer you know is wrong - you should say how you know.
The assessment of the problem changes whether you got an answer different from a model answer, and answer that a human marked wrong, and an answer that a computer marked wrong.

You should also always show you working and reasoning ... seeing correct calculations and a "the computer rejected the result" would have got you specific and helpful advise right away.
 

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