Measurement accuracy or variation

This is important to note as the accuracy of these constants relies on the accuracy of h, which is currently the most accurately measured physical constant.
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I find the values of the fundamental constants here
https://physics.nist.gov/cuu/Constants/
In anticipation of the data of 2022, I want to clarify one point.

Planck's constant is related by an exact expression to some other fundamental quantities:
$$h = \frac{\alpha^2 m_e с^2}{2R_c}\qquad (1)$$

c = 299 792 458 m⁄s (exact)
me = 9.109 383 7015(28)∙10-31 kg
α = 7.297 352 5693(11)∙10-3
Rc =3.289 841 960 2508(64)∙1015 s

The SI units are defined in such a way that, when the Planck constant is expressed in SI units, it has the exact value h = 6.62607015×10-34 J⋅Hz-1

As of 2018, R and electron spin g-factor are the most accurately measured physical constants.
https://en.wikipedia.org/wiki/Rydberg_constant

2010 R= 10 973 731.568 539 (55) m-1
2014 R=10 973 731.568 508 (65) m-1
2018 R=10 973 731.568 160 (21) m-1

We see a big leap in value.
So the previous accuracy is a bluff.
Maybe I'm wrong , but its related to the problem called Proton radius puzzle

Which value in the above formula (1) will be determined experimentally, and which one is calculated if h(exact), c(exact) ?
 
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The value of Planck's constant, h, will be determined experimentally. The values of the other fundamental constants, c, me, α, and Rc, will be calculated from the exact value of h, c, and the measured values of me, α, and Rc.
 

FAQ: Measurement accuracy or variation

1. What is measurement accuracy?

Measurement accuracy refers to how close a measured value is to the true or accepted value. It is a measure of how well a measurement represents the true value of the quantity being measured.

2. How is measurement accuracy different from measurement precision?

Measurement precision refers to how close a series of measurements are to each other, regardless of their accuracy. It is a measure of the repeatability or consistency of a measurement. Accuracy and precision are both important factors in determining the overall quality of a measurement.

3. What is measurement variation?

Measurement variation refers to the amount of difference or variability in a set of measurements. It can be caused by factors such as instrument error, human error, or natural variability in the quantity being measured. Reducing measurement variation is important for improving the accuracy and precision of measurements.

4. How is measurement accuracy evaluated?

Measurement accuracy is evaluated by comparing the measured value to a known or accepted value. This can be done through calibration, where the instrument is tested against a standard, or through interlaboratory comparisons, where multiple labs measure the same sample and compare results.

5. What are some common sources of measurement error?

Some common sources of measurement error include instrument error, human error, environmental conditions, and natural variation in the quantity being measured. It is important to identify and minimize these sources of error in order to improve measurement accuracy and precision.

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