WARNING: MEASUREMENTS ARE UNCERTAIN.

IS MEASUREMENT RELATIVE?

We're humans, the contemplators of the universe. That's it. We love, or should I say it is natural for us to invent things that were not here, not within reach to make our lives easier. Let me cite an example, alphabets. Language is an indispensable part of our existence. Can you imagine a language which didn't need the help of a symbol for giving meaning to every single word in it? It's difficult to think one, right? Another thing we wonderfully "made-up" although many of us hate this.. mathematics. We cannot deny that we were enlightened on how the universe rationally moves or goes on by using this wonderful invention. We're in great need of understanding the whole truth of our dear universe. I guess that was delivered too sentimental. In addition to that, since I'm taking up Physics, it's important to quantify things that are measurable, if it's not measurable, it's not-so-physics. Anyway, why am I saying these things? How do these answer the BIG question above? On my last post, I mentioned that measurements are products of arbitration. Which means that.. [look at the title of this new blog -- the one with the "warning"].

activity 1
 Last time, I said the three major factors that affect your measurement according on what I've learned during our discussion or basically what I wrote on my notes:

1.  The nature of the quantity being measured (e.g. a person is measuring a roughly surfaced object using a ruler *goodluck*)
2. Judgement of the experimenter (e.g.  the measured data lies between 1 m and 2 m and the experimenter decided to report the data as 1.500 m)
3. Limitations of the device (e.g. some graduated cylinders have more detailed calibrations than others)

  With these factors in mind, I realized the point I brought up, that measurements are the results of arbitration. Yes, they're just made up. However, these data gathered are very important for the technical people.

 

activity 2

  

  I already made a short narrative on how we measured every, single rice grain by using a Vernier caliper and it mainly focuses about patience, data, patience, stuck fingers, patience, oh well. The real challenge was measuring the grains using this thing: 

                                                   (image from headway-tech.com) 

A micrometer caliper. Luckily, last meeting, we had the chance to use this as a measuring tool. Although, this looks harder to use than the Vernier caliper, we (our group) ironically measured more grains using this kind. I bet we learned to be more focus this time. Anyway, like our first measurements using the Vernier, the data we collected using the micrometer corresponds to what we expected. I think 90% of the grains measured as 7.00+ mm. The other 10% are mostly dominated by the 6.00+ mm, otherwise it's in the 8.00+ mm line.

Last of the three factors that affect the measurement of an object tells us that no measuring device can be so accurate. Hence, those two kinds of calipers we used, also have their own margin of error. The Vernier caliper has an error of ± 0.02 mm, while the micrometer has ± 0.01 mm. It means that micrometer is more accurate compared to  the Vernier by 0.01mm, which is kinda big difference. 

I think the average length of the rice grain is the data of an international research which says that length of the rice grain is 7.09± 0.36 mm. This, I believe, is true because they have measured a lot of rice grain. Our professor said that they were able to measure a thousand rice grain.A matter of 950 grain-difference to our data. So obviously, they got a wider gathering of data, and a more acceptable mean. I think the next question may be: What is the variant of rice they measured?