A measurement instrument is a device used to sample physical observations. Examples include pressure sensors, thermocouples, etc.
Questions tagged [instrument]
111 questions
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How do laser "tape measures" work?
There is a device available for about $\$40$, which fits in the palm of the hand, runs on two AA batteries, and can measure distances up to $50\,{\rm ft}$ to an accuracy of $\sim \frac{1}{8}''$ ($\sim 3\,{\rm mm}$).
Light travels $300,000\,{\rm…
Anthony X
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Please help identify this physics apparatus!
This was my grandfather’s and have no idea what it is only that it is some piece of physics equipment!
The main black cylinder doesn’t seem like it wants to rotate but not sure if it should?
user37250
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Can you tell me what is the name of this scientific instrument?
Hello i need help to identify this old instrument.
I only have this photo.
Can you help me?
8
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What is a spectrometer, and why are they so useful in science?
I've heard reference to many telescope and spacecraft that have a device known as a spectrometer, and I'm curious, what is the purpose of these device? What's the working principal behind them and what do we use them for?
PearsonArtPhoto
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What physical state of a wound string corresponds to a 'tuned' string?
Many instruments can be strung with strings comprised of a solid core and wound with another metal wire, e.g. the viola. I was wondering about the physical state of wound strings when they are 'in tune'.
My thought was this could be when the wires…
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What is meant by precision of a measuring instrument?
I came across many definitions of the precision of a measuring instrument such as, "a precise measuring tool is one that can measure values in very small increments" and "The precision of the instrument that is used to take a measurement is…
Altair25
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Why must an integrating sphere be a sphere?
Why must an integrating sphere be a sphere? Why can't it be an integrating cube? What is the difference? Could I use a cube to measure total illuminance like an integrating sphere does?
dartheize
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What is the difference between a photon's phase and polarization?
When talking about a photon emitted by a laser device, what is the difference between phase and polarization?
Is it redundant to specify both the polarization and the wavefunction's phase?
Does a phase modulator affect both?
Context: This question…
João Bravo
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What is the difference between a galvanometer, an ammeter and a voltmeter?
I'm looking for basic differences b/w the three with respect to nature of the circuit as well i.e either it is connected in parallel or series, and also the reason as to why they're connected the way they are? In what cases are these three used?
Shanzaasad
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Formula for lens periscope
I want to build a periscope.
To my great surprise even after intense googling I could find little relevant information about periscopes anywhere on the internet.
Let's say I want to build a periscope with height h, apparent height h1, diameter d…
daniel.sedlacek
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How is the Hanbury-Brown and Twiss effect used to measure the size of stars?
I understand what an Hanbury Brown and Twiss (HBT) interferometer does, but how can this be used to measure the apparent angular diameter of some object?
What is the mathematical explaination?
Dan
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Would a microscope behave as a telescope if we brought the objective lens closer to the eye piece?
I believe there are two ways to transform a compound microscope to a telescope. Either you bring the the objective lens closer to the eyepiece(what i think) or you increase the focal length(what i read). Here's my reason-
This is a a compound…
Khushiv Batra
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Why bulk of HPGe detectors is doped?
When I am looking at schematic diagrams of HPGe gamma spectrometer detectors (like this Ortec GLP one), it is often mentioned that bulk of Ge is doped. In this example - P-type doped. Is there a reason why doped germanium is used rather than truly…
BarsMonster
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What is the meaning of "Dual Accuracy" on this datasheet?
I'm trying to determine the uncertainty in some of my measurements, and one of the variables I measure is temperature, using a Tenma 72-7715 thermometer. I looked up the datasheet to find the measurement uncertainty of this instrument, and this is…
probablysid
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Zero Error of Screw Gauge
Consider a screw gauge of 50 divisions on the circular scale. Till now I have used the following method to account for zero error in it.
If $x^{th}$ division on the circular scale coincides with the zero on the main scale , then zero error,$Z$ is…
Tony Stark
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