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Significant figures

  1. Aug 30, 2009 #1

    Andrew Mason

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    A professor sets a 34 hour take-home exam and states: "Please note the Monday, 9 AM deadline".

    A student hands the paper in at 9:12 AM on Monday.

    Has the student missed the deadline? Explain.

    AM
     
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  3. Aug 30, 2009 #2

    Integral

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    Yes,

    If the prof had ment 9:30 or 9:15 he would have not said 9am.
     
  4. Aug 30, 2009 #3

    Andrew Mason

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    So you are saying that 9 AM is exactly the same as 9:00 AM?

    What if he had said 9:00 AM and the student submitted it at 9:00:12 AM (ie. 12 seconds after 9:00:00 AM).

    AM
     
    Last edited: Aug 30, 2009
  5. Aug 30, 2009 #4

    Integral

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    Hard to answer. Check your watch against your friends, If you all agree within 15min I would be surprised. I guess the only one that matters here is the profs watch, and how generous he is feeling.
     
  6. Aug 31, 2009 #5
    Just out of curiosity, is this a real life scenario or just a problem?
     
  7. Aug 31, 2009 #6

    D H

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    5/100. Zero for handing the exam in after the deadline, five for creatively answering the (unasked) bonus question, "Why did you hand this in late?"
     
  8. Aug 31, 2009 #7
    9AM means exactly 9AM, not 1ns later or before. However I think most professors would accept a paper 12seconds late. If you missed the deadline by 12minutes the professor might still accept the paper, but if he does then it's because he's friendly not because he has to. Significant figures is nothing but a convenient convention, and while many engineers and some scientists implicitly assumes that any number has an uncertainty associated with it that is only because both parts agree that is what is meant. When someone, e.g. your professor, tells you a time he does not mean 9hr +- 6min and you should not take it as such. To most people 9AM, 9:00AM, 9:00:00AM and 9:00:00.000AM are all the same. I hope this isn't a real-life problem as it sucks to have done the work and then get no credit; especially if you genuinely misunderstood the professor's instructions. If it is a real-life problem I hope you can explain to the professor that you misunderstood his instructions.

    I once had an experience that taught me to always turn in at least a while before the deadline. I tried to hand in my 1-week paper 5 minutes before the deadline, but the teacher refused to accept it and went on a rant about how disrespectful it was to turn it in in the last minute when you had had all week. After 10 minutes of argument he stated that if I hadn't been late then, then at least now I was so he couldn't accept it. Finally he offered to take it if I would sign that I had handed it in 5 minutes late. Since it wouldn't affect me in any way and I realized the argument was going nowhere I simply agreed (I probably could have complained to someone else, but it was my senior year of high school and complaining might have delayed my graduation due to the fact that I could not get a final grade till the matter was sorted out).
     
  9. Aug 31, 2009 #8

    arildno

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    If I sit for a 6-hour exam, am I then entitled to write in excess of that time limit for more minutes than if I only sat for a 2-hour exam?
     
  10. Aug 31, 2009 #9

    HallsofIvy

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    If you write for any exam, you are not entitled to write in excess of the time limit at all! That's what "time limit" means.
     
  11. Aug 31, 2009 #10

    arildno

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    Well, then, should the "grace period" beyond the time limit be longer for a 6-hour exam than for a 2-hour exam?

    Say, three times as long?
     
  12. Aug 31, 2009 #11

    Andrew Mason

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    The issue arose with a client's case. We are trying to develop a legal argument to get the college to back down. I wanted to see if the significant figures argument might fly.

    AM
     
  13. Aug 31, 2009 #12

    Andrew Mason

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    Generally, professors will allow some leeway with take-home exams or assess penalties for lateness - and make these rules clear at the outset. The student is not expected to work the entire 34 hours on the take-home exam, so the time limit is not a critical factor. In fact, the take home exam is used precisely because time is not a critical factor. Hence my argument about significant figures.

    AM
     
  14. Aug 31, 2009 #13
    If the world were so rigid, it would snap in two.

    Twelve minutes means so little in the grand scheme of things. As a length of time, it makes up less than one part in one hundred thousand of a standard 18-week semester. To apply so much weight as to potentially fail a student over such a small slice of time is unreasonable by any standard which takes into account human nature.

    Of course, on the other hand, it's a slippery slope. Cases should be delegated individually, and the professor should take stronger stances against repeat offenders. But in the end, the penalty should be proportional to the offense.

    Some professors use arguments like "it wouldn't be fair to the other students", but in this kind of case, the extra twelve minutes were probably spent fighting off the alarm clock, not perfecting the wording on the final proof of the test.

    Also, this doesn't belong in this forum.
     
  15. Sep 1, 2009 #14

    Andrew Mason

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    This was intended as a discussion of significant figures in relation to time.

    In my view there is an argument that if you use as a deadline "9 AM" you are not intending to worry about a few minutes so long as it is not 10 AM. If I had a clock that only measured hours, at 9:12 AM it would read "9 AM". So an exam submitted at 9:12 AM would be submitted at "9 AM" on that clock.

    AM
     
  16. Sep 1, 2009 #15

    arildno

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    Then I would advice you to utilize the distinction "nine sharp" versus just "nine".
    (Isn't that what you use in English?)

    That is, to show that we DO have common words indicating a minute-exact time limit, and that the professor did NOT use such words.
     
  17. Sep 1, 2009 #16

    HallsofIvy

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    No doubt. My problem was with the word "entitled". Nothing was said about anything being made "clear at the outset".

    I would interpret "9 A.M." as an integer value. And "significant figures" apply to apply to measured real values, not counted integer values.
     
  18. Sep 1, 2009 #17
    I think this is correct.

    Now to deviate from the intent of the thread, I had a professor assign a term paper. He said "They must be turned in on April 21. For those of you who will need an extension they are due on the 14th, and if you come to me then and beg, I will grant you a one week extension..."

    School teaches us many things. Physics, math, and how to get along in the world. If you are 12 minutes late to the gate you will miss your flight, if you're 12 minutes late to a job interview you won't get the job, if you're 12 minutes late to your buddy's party who cares? If you are a grown-up you should know the difference.
     
    Last edited: Sep 1, 2009
  19. Sep 1, 2009 #18

    Andrew Mason

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    And using that approach, 9:12 AM is 9 AM as an integer value. I like it.

    AM
     
  20. Sep 1, 2009 #19

    Andrew Mason

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    All fine points, which again illustrate significant figures. Where do airlines schedule flight times without the minutes eg "9 AM" to mean "9:23 AM"?

    Besides, there are ways to teach lessons without causing a student to lose a year and a scholarship of $72k because he handed something in 12 minutes late. Incidentally, he emailed it at 8:51 AM and made no changes after that time. The prof would not accept email submissions so he had to deliver it and it took 21 minutes to do that.

    AM
     
  21. Sep 1, 2009 #20
    Never. Just like the professor would never say 9 AM if it could be handed in at 9:15 AM.

    Of course, that's the argument that you would use if you're one of those people that says "Well, technically,..." as a way to justify an annoying or inane remark. I think your whole significant figures thing is misguided and reminds me of some sort of youtube conversation. Arrange a hearing with the professor and some school officials, and unless there's some good reason the professor can't accept a paper that's 15 minutes late, the reasonable, adult thing to do is to take it and at most take some points off.

    This isn't first grade where you have to teach life lessons. Everyone's an adult and everyone has been late at some point.
     
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