All Questions
Tagged with conventions error-analysis
53
questions
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Significant figures when product is more by a factor of 10
A rectangular plate has a length of 21.3 cm and a width of 9.8 cm. Calculate the area of the plate.
A straightforward question, which you multiply and arrive at 208.74 cm2. Taking significant figures ...
- 103
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1
answer
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Are zeros to the right really significant? [duplicate]
In one of YouTube lectures about significant digits I saw this:
I was completely shocked. Both scientific notation numbers when converted to integer would represent same quantity of $1200 \text{kg}$ ...
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1
answer
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How to add and subtract significant figures?
There are actually two ways given to add or subtract significant figures in different books .In books like concepts of Physics by HC Verma it is written that round of the numbers given first and then ...
3
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1
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Why is the term 'Accuracy of 1 part in $x$' used?
My question stems from how we measure the accuracy of Caesium clocks. Most Caesium clocks are said to have an accuracy of '$1$ part in $10^{14}$.'
I understand that the terminology means to convey ...
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1
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Significant Figures when dealing with bearings
Significant figures are used to ensure that the value is precise, and fall in within error in the positive and negative direction.
327 degrees true can also be written as N33degreesW. As such, would ...
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1
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Significant figures in simple calculations
I have the resistivity of a material $\rho = 7.4 \times 10^{-7}$ $\Omega\cdot$m and I want to compute its conductivity $\sigma = 1/\rho$.
Straight forward calculation gives (up to 3 decimals) $\sigma =...
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9
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5
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451
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Significant figures and multiplication
Suppose the volume of a cylinder with diameter $d=$11.92 ± 0.01 mm and height $h=$38.06 ± 0.02 mm. Calculating $\frac{\pi d^2h}{4}$, the volume is 4247.282773 mm^3, without rounding off. Now, I read ...
4
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2
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How to understand measurement uncertainty (error) from scientific papers in this form 6.67430(15)?
My question is very practical and is about real physical value measurements and related uncertainty.
As I understand now most scientists work with Student's t-distribution when they are estimating ...
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How to report a numerical result?
There is a problem of measurement of speed of sound in steel. It is given that the speed of sound in air is 343 m/s and the length of the steel rod is 100 m. The difference in time for the sound to ...
2
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1
answer
45
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Degree of accuracy to express $T$?
I conducted a pendulum experiment and here are my results:
10T / s:
( The time taken for 10 oscillations measured on a stopwatch that only shows the time to 2 decimal places. Measured in seconds )
For ...
3
votes
2
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98
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Expressing answer to correct degree of accuracy
In Physics when we multiply or add two quantities with different significant figures, why do we express our answer with the lowest significant figures? Consider we measured current to be 0.65A and we ...
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2
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63
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Uncertain figures
I have doubts about the definition of uncertain figure.
If I have the following measurement (2.7 ± 0.1) m it means that the true value of the quantity is between 2.6 and 2.8 and therefore the ...
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I have a list of values from an experement. I want to calculate the best estimate for the mean, how accurately should I quote these values?
Imagine a set of data such as the following: $16,15,14,14,16,17$. To find the best estimate for the mean it is usual to find the mean and quote an uncertainty given by the sample standard deviation ...
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1
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1
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What are the significant digits, when the standard deviation is larger than the value?
Let's say I have some quantity $a = 1.234\,a.u.$ with a standard deviation of $\sigma = 123.4\,a.u.$. How do I express the uncertainty in this case?
$a = (1.2\pm 123.4)\,a.u.$
$a = (0.0\pm1.2)\...
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Rules of significant figures, precision, and uncertainty
In the physical sciences (which are physics, chemistry, astronomy, materials science, etc.), we learned that the uncertainty is +/- the smallest unit (which is 1) of the last significant figure if the ...
