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I think that 3 gram minimum is inaccurate, and is resulting in extra confusion. I estimate the container to be closer to 2 grams.
hmmmm. these are the values my teacher gave me...Charles Link said:I think that 3 gram minimum is inaccurate, and is resulting in extra confusion. I estimate the container to be closer to 2 grams.
Can't be 7 marbles by definition. Mass of marble is more like 4.5, Try another guess. It won't be perfect.orangegalaxies said:Largest mass: 31.9 g
Approx weight of one marble: 4 g
Mass of empty container: minimum of 3 g
(31.9 - 3)/4 = 7 marbles in largest container
This is wrong, I don't follow what you are saying, can you please explain?
Can you explain how you got 4.5 g?hutchphd said:Apologies. You almost got it but you need to choose best values from noisy data:
Can't be 7 marbles by definition. Mass of marble is more like 4.5, Try another guess. It won't be perfect.
Now make guess and plot mass vs # marbles for all data points.
Yeah you're right that is a pattermCharles Link said:If you look at the data, at first glance, (I'm sure you observed it as well), there appears to be increments of between 4.5 and 5 grams. There is a jump from 11 to 21, but with a small sample, it's not surprising that the 16 is absent.
I disagree I think it is more like 6g. The problem says >3.Charles Link said:I think that 3 gram minimum is inaccurate, and is resulting in extra confusion. I estimate the container to be closer to 2 grams.
see my post 42 :)hutchphd said:I disagree I think it is more like 6g. The problem says >3.
This is also true yeahCharles Link said:I just spotted something else=they give you the weight of the container to be at least 3 grams=it might even be large enough to make the 11 g have just one marble=my previous post on this being inaccurate and possibly 2 grams was incorrect.
graph the differences in masses?hutchphd said:Yes Now the OP needs to graph the data, draw the best linear fit. Slope gives marble mass, intercept gives container mass
in your previous post, is there any way you found the marble mass = 4.5 g? calculations i meanhutchphd said:Your eyeball and ruler will draw the "best" line pretty well. Gives the best fit to all the data.
sure, but as Charles mentioned, y=total measured mass vs. x=number of marbles. To find the number of marbles I need the mass of one so I wanted to know how you can say its 4.5 ghutchphd said:Rough graph in my head. Do the graph. Excel?
The increments are about 4.5 other than the missing 16. This is a very simple graph to draw by hand=if you have some graph paper it helps. Otherwise EXCEL is often used, but that can take some work to learn.orangegalaxies said:in your previous post, is there any way you found the marble mass = 4.5 g? calculations i mean
Hello, after graphing, I got a slope of 4.49992 and a y-intercept of 3.00000061. Is this reasonable?hutchphd said:You only need the integer number of marbles to plot the data. I guessed the 4.5 because it seemed to give integers within reasonable error limits. The error in the mass obtained from the best fit line (slope) from the graph should be good to a few percent. This slope in the Millikan oil drop experiment gave Millikan the charge increment for little balls of oil, electron by electron as he irradiated them). A truly beautiful experiment.
Incidentally it is possible that all the changes in the graph involved always moving 2 marbles (or3 or4) but it is less and less likely More data would make it more certain.
Please draw the graph. I don't think you graphed it, because I just graphed it, and I got round numbers, but not real close to 4.5, and certainly not 3 for the other number. The accuracy is only one decimal place or thereabouts.orangegalaxies said:Hello, after graphing, I got a slope of 4.49992 and a y-intercept of 3.00000061. Is this reasonable?
The graph shows this answer very clearly, and I'm hoping the OP will draw the graph like I did to see this for himself.hutchphd said:And I think the first data cluster is for n=1 marble so the mass of the container is ~6g
To be honest, in the 63 posts so far, there have not been many contributions from you. You need to show a better grasp of the problem yourself.orangegalaxies said:thanks guys, i don't have any graph paper on me so i tried to graph it digitally which didn't work apparently. i will get some today to finish it off. would you be able to help me answer these questions?
- Would having more containers make this easier?: i think so since it would give more data right?
- Would having a large variety of quantity (eg: having max of 7-11 marbles instead of 5-6) make this easier?
- How does this relate to Millikan's experiment?
- What are some sources of error?: damage to either the container/marbles which would alter their mass?
okay thanks. i was told to solve it a different way by my teacher so i tried doing that but the other contributors said to do it another way which i obviously don't know how to do therefore i am unable to contribute. i can only grasp the problem if someone explains which is not the case since it seems more like everyone is asking me why I'm not doing this a certain way instead of telling me WHY AND HOW i am supposed to do it that way.PeroK said:To be honest, in the 63 posts so far, there have not been many contributions from you. You need to show a better grasp of the problem yourself.
You need to take responsibility for your own academic progress. I'm not convinced that it's your teacher's fault - or the people who've posted ideas or suggestions here.orangegalaxies said:okay thanks. i was told to solve it a different way by my teacher so i tried doing that but the other contributors said to do it another way which i obviously don't know how to do therefore i am unable to contribute
Please read my post 58. There is a shortcut presented there that you can do without graph paper that is reasonably accurate.orangegalaxies said:okay thanks. i was told to solve it a different way by my teacher so i tried doing that but the other contributors said to do it another way which i obviously don't know how to do therefore i am unable to contribute. i can only grasp the problem if someone explains which is not the case since it seems more like everyone is asking me why I'm not doing this a certain way instead of telling me WHY AND HOW i am supposed to do it that way.
i'm not saying it's their fault. my teacher doesn't offer any support to their students, i can't teach myself everything through youtube videos and tutorials. i need someone to explain things to me which is why i came here. i am new to these concepts, if someone tells me something once, i won't just take it to be correct, i need to understand why that method was used which takes time.PeroK said:You need to take responsibility for your own academic progress. I'm not convinced that it's your teacher's fault - or the people who've posted ideas or suggestions here.
Here's the first thing I said on this thread:orangegalaxies said:i'm not saying it's their fault. my teacher doesn't offer any support to their students, i can't teach myself everything through youtube videos and tutorials. i need someone to explain things to me which is why i came here. i am new to these concepts, if someone tells me something once, i won't just take it to be correct, i need to understand why that method was used which takes time.
PeroK said:This is perhaps a tough question, as you may actually have to think about what to do.
yes i don't need you to, thanks.PeroK said:Here's the first thing I said on this thread:
We can't think for you: you have to do that yourself.