Questions tagged [measurements]
For questions related to methods, analysis, accuracy, presentation, or interpretation of measurements. It is not intended for abstract quantum measurement questions such as how a wave function collapses during measurement or how the Heisenberg uncertainty principle constrains quantum measurements.
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Continued calibration of atomic clocks
First off I am not well versed in physics, but as I understand things the second is defined by the ceasium fountain clock which is calibrated as follows How was the first atomic clock calibrated?. Now ...
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Determine thermal emissivity of material
Is there a practical way of determining it without a lab setup?
interested in Aluminum alloys ADC-10 and ADC-12
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What exactly does the quantum mutual information measure? [duplicate]
Quantum mutual information (QMI) is often said to be the quantum mechanical analog of Shannon mutual information (MI).
I realize they can be written with the same formula:
$$S_x+S_y-S_{xy} \ ,$$
where ...
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Vernier Caliper Measurement [duplicate]
My doubt is regarding the formula for measurement using a vernier caliper. In my class we were taught the following formula:
$Reading = MSR + n(LC)$ (p)
(here MSR stands for main scale reading and LC ...
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Relationship between density and temperature - How to know the precise temperature at which a bell inside a Galileo Thermometer will sink?
A Galileo Thermometer consists of bells placed inside a tube that's filled with liquid. As the temperature increases, the fluid density decreases. This leads to a decrease in the buoyant force, and ...
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If gravitation is negligible for small masses, how was Cavendish's experiment successful with balls much smaller than celestial objects?
If gravitation is negligible for small masses, then how was Cavendish's experiment a success since the balls used were very small compared to the sizes of celestial objects?
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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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Does changing units affect Significant Figures
Does changing the unit of a physical quantity has no influence whatsoever on the number of significant figures?
Suppose the mass of a particle is given as 0.060kg
0.060 has 2 significant figures as ...
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States of entangled particles after no/partial/full measurement
I'm getting contradictory information from the internet concerning entangled particles, measurement, and state knowledge that I'm hoping can be cleared up with a simple setup.
Say we have a source of ...
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Why is my pyrgeometer calibrated as if it has $a >1$ emissivity?
I've acquired an SL-510-SS upward-looking pyrgeometer.
In the manual it gives the formula for how to compute the downwelling infrared it picks up:
Clearly the $k_2$ coefficient is the emissivity of ...
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Why is the uncertainty of the Gravitational Constant $G$ many orders of magnitude larger than that of other important fundamental constants?
Why is the numerical range of uncertainty of the Gravitational Constant $G$ many orders of magnitude larger than that of other important fundamental constants?
What are the challenges in precise ...
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How were angles measured in ancient times?
What is one degree (angle measurement)? I know that we calculate one second using atomic clock, one kilogram using Planck's constant, one meter using speed of light but how do we define one degree? If ...
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The Principle of Homogeneity of dimensions states that you can add,subtract quantities with same dimensions but we cannot add a constant with an angle
Both a constant and a plane and solid angle are dimensionless ie they have the same dimensions , so according to principle of homogeneity should you not be able to equate them ?
But it would be absurd ...
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How to measure the vibration of an object on a video shot at high speed camere?
I have a video fragment which I split into frames (pictures). I use them in pairs (1 frame with 2, 2 with 3, etc.) to find shifts on x and y axes (i.e. how much I need to shift 1 frame to make it like ...
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Vernier Calliper Reading and significant figures
What if in Vernier Calliper the Vernier Scale division (zero mark) coincides with the Main Scale Reading(MSR) will we take 'n' as 0 or 10 in the formula Reading = MSR + LC (Least Count) x n?
1) If we ...
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